[net-next-2.6.git] / arch / sh / kernel / irq.c

/*
 * linux/arch/sh/kernel/irq.c
 *
 *	Copyright (C) 1992, 1998 Linus Torvalds, Ingo Molnar
 *
 *
 * SuperH version:  Copyright (C) 1999  Niibe Yutaka
 */
#include <linux/irq.h>
#include <linux/interrupt.h>
#include <linux/module.h>
#include <linux/kernel_stat.h>
#include <linux/seq_file.h>
#include <linux/ftrace.h>
#include <linux/delay.h>
#include <asm/processor.h>
#include <asm/machvec.h>
#include <asm/uaccess.h>
#include <asm/thread_info.h>
#include <cpu/mmu_context.h>

atomic_t irq_err_count;

/*
 * 'what should we do if we get a hw irq event on an illegal vector'.
 * each architecture has to answer this themselves, it doesn't deserve
 * a generic callback i think.
 */
void ack_bad_irq(unsigned int irq)
{
	atomic_inc(&irq_err_count);
	printk("unexpected IRQ trap at vector %02x\n", irq);
}

#if defined(CONFIG_PROC_FS)
/*
 * /proc/interrupts printing:
 */
static int show_other_interrupts(struct seq_file *p, int prec)
{
	int j;

	seq_printf(p, "%*s: ", prec, "NMI");
	for_each_online_cpu(j)
		seq_printf(p, "%10u ", irq_stat[j].__nmi_count);
	seq_printf(p, "  Non-maskable interrupts\n");

	seq_printf(p, "%*s: %10u\n", prec, "ERR", atomic_read(&irq_err_count));

	return 0;
}

int show_interrupts(struct seq_file *p, void *v)
{
	unsigned long flags, any_count = 0;
	int i = *(loff_t *)v, j, prec;
	struct irqaction *action;
	struct irq_desc *desc;
	struct irq_data *data;
	struct irq_chip *chip;

	if (i > nr_irqs)
		return 0;

	for (prec = 3, j = 1000; prec < 10 && j <= nr_irqs; ++prec)
		j *= 10;

	if (i == nr_irqs)
		return show_other_interrupts(p, prec);

	if (i == 0) {
		seq_printf(p, "%*s", prec + 8, "");
		for_each_online_cpu(j)
			seq_printf(p, "CPU%-8d", j);
		seq_putc(p, '\n');
	}

	desc = irq_to_desc(i);
	if (!desc)
		return 0;

	data = irq_get_irq_data(i);
	chip = irq_data_get_irq_chip(data);

	raw_spin_lock_irqsave(&desc->lock, flags);
	for_each_online_cpu(j)
		any_count |= kstat_irqs_cpu(i, j);
	action = desc->action;
	if (!action && !any_count)
		goto out;

	seq_printf(p, "%*d: ", prec, i);
	for_each_online_cpu(j)
		seq_printf(p, "%10u ", kstat_irqs_cpu(i, j));
	seq_printf(p, " %14s", chip->name);
	seq_printf(p, "-%-8s", desc->name);

	if (action) {
		seq_printf(p, "  %s", action->name);
		while ((action = action->next) != NULL)
			seq_printf(p, ", %s", action->name);
	}

	seq_putc(p, '\n');
out:
	raw_spin_unlock_irqrestore(&desc->lock, flags);
	return 0;
}
#endif

#ifdef CONFIG_IRQSTACKS
/*
 * per-CPU IRQ handling contexts (thread information and stack)
 */
union irq_ctx {
	struct thread_info	tinfo;
	u32			stack[THREAD_SIZE/sizeof(u32)];
};

static union irq_ctx *hardirq_ctx[NR_CPUS] __read_mostly;
static union irq_ctx *softirq_ctx[NR_CPUS] __read_mostly;

static char softirq_stack[NR_CPUS * THREAD_SIZE] __page_aligned_bss;
static char hardirq_stack[NR_CPUS * THREAD_SIZE] __page_aligned_bss;

static inline void handle_one_irq(unsigned int irq)
{
	union irq_ctx *curctx, *irqctx;

	curctx = (union irq_ctx *)current_thread_info();
	irqctx = hardirq_ctx[smp_processor_id()];

	/*
	 * this is where we switch to the IRQ stack. However, if we are
	 * already using the IRQ stack (because we interrupted a hardirq
	 * handler) we can't do that and just have to keep using the
	 * current stack (which is the irq stack already after all)
	 */
	if (curctx != irqctx) {
		u32 *isp;

		isp = (u32 *)((char *)irqctx + sizeof(*irqctx));
		irqctx->tinfo.task = curctx->tinfo.task;
		irqctx->tinfo.previous_sp = current_stack_pointer;

		/*
		 * Copy the softirq bits in preempt_count so that the
		 * softirq checks work in the hardirq context.
		 */
		irqctx->tinfo.preempt_count =
			(irqctx->tinfo.preempt_count & ~SOFTIRQ_MASK) |
			(curctx->tinfo.preempt_count & SOFTIRQ_MASK);

		__asm__ __volatile__ (
			"mov	%0, r4		\n"
			"mov	r15, r8		\n"
			"jsr	@%1		\n"
			/* swith to the irq stack */
			" mov	%2, r15		\n"
			/* restore the stack (ring zero) */
			"mov	r8, r15		\n"
			: /* no outputs */
			: "r" (irq), "r" (generic_handle_irq), "r" (isp)
			: "memory", "r0", "r1", "r2", "r3", "r4",
			  "r5", "r6", "r7", "r8", "t", "pr"
		);
	} else
		generic_handle_irq(irq);
}

/*
 * allocate per-cpu stacks for hardirq and for softirq processing
 */
void irq_ctx_init(int cpu)
{
	union irq_ctx *irqctx;

	if (hardirq_ctx[cpu])
		return;

	irqctx = (union irq_ctx *)&hardirq_stack[cpu * THREAD_SIZE];
	irqctx->tinfo.task		= NULL;
	irqctx->tinfo.exec_domain	= NULL;
	irqctx->tinfo.cpu		= cpu;
	irqctx->tinfo.preempt_count	= HARDIRQ_OFFSET;
	irqctx->tinfo.addr_limit	= MAKE_MM_SEG(0);

	hardirq_ctx[cpu] = irqctx;

	irqctx = (union irq_ctx *)&softirq_stack[cpu * THREAD_SIZE];
	irqctx->tinfo.task		= NULL;
	irqctx->tinfo.exec_domain	= NULL;
	irqctx->tinfo.cpu		= cpu;
	irqctx->tinfo.preempt_count	= 0;
	irqctx->tinfo.addr_limit	= MAKE_MM_SEG(0);

	softirq_ctx[cpu] = irqctx;

	printk("CPU %u irqstacks, hard=%p soft=%p\n",
		cpu, hardirq_ctx[cpu], softirq_ctx[cpu]);
}

void irq_ctx_exit(int cpu)
{
	hardirq_ctx[cpu] = NULL;
}

asmlinkage void do_softirq(void)
{
	unsigned long flags;
	struct thread_info *curctx;
	union irq_ctx *irqctx;
	u32 *isp;

	if (in_interrupt())
		return;

	local_irq_save(flags);

	if (local_softirq_pending()) {
		curctx = current_thread_info();
		irqctx = softirq_ctx[smp_processor_id()];
		irqctx->tinfo.task = curctx->task;
		irqctx->tinfo.previous_sp = current_stack_pointer;

		/* build the stack frame on the softirq stack */
		isp = (u32 *)((char *)irqctx + sizeof(*irqctx));

		__asm__ __volatile__ (
			"mov	r15, r9		\n"
			"jsr	@%0		\n"
			/* switch to the softirq stack */
			" mov	%1, r15		\n"
			/* restore the thread stack */
			"mov	r9, r15		\n"
			: /* no outputs */
			: "r" (__do_softirq), "r" (isp)
			: "memory", "r0", "r1", "r2", "r3", "r4",
			  "r5", "r6", "r7", "r8", "r9", "r15", "t", "pr"
		);

		/*
		 * Shouldnt happen, we returned above if in_interrupt():
		 */
		WARN_ON_ONCE(softirq_count());
	}

	local_irq_restore(flags);
}
#else
static inline void handle_one_irq(unsigned int irq)
{
	generic_handle_irq(irq);
}
#endif

asmlinkage __irq_entry int do_IRQ(unsigned int irq, struct pt_regs *regs)
{
	struct pt_regs *old_regs = set_irq_regs(regs);

	irq_enter();

	irq = irq_demux(irq_lookup(irq));

	if (irq != NO_IRQ_IGNORE) {
		handle_one_irq(irq);
		irq_finish(irq);
	}

	irq_exit();

	set_irq_regs(old_regs);

	return IRQ_HANDLED;
}

void __init init_IRQ(void)
{
	plat_irq_setup();

	/* Perform the machine specific initialisation */
	if (sh_mv.mv_init_irq)
		sh_mv.mv_init_irq();

	intc_finalize();

	irq_ctx_init(smp_processor_id());
}

#ifdef CONFIG_SPARSE_IRQ
int __init arch_probe_nr_irqs(void)
{
	nr_irqs = sh_mv.mv_nr_irqs;
	return NR_IRQS_LEGACY;
}
#endif

#ifdef CONFIG_HOTPLUG_CPU
static void route_irq(struct irq_data *data, unsigned int irq, unsigned int cpu)
{
	struct irq_desc *desc = irq_to_desc(irq);
	struct irq_chip *chip = irq_data_get_irq_chip(data);

	printk(KERN_INFO "IRQ%u: moving from cpu%u to cpu%u\n",
	       irq, data->node, cpu);

	raw_spin_lock_irq(&desc->lock);
	chip->irq_set_affinity(data, cpumask_of(cpu), false);
	raw_spin_unlock_irq(&desc->lock);
}

/*
 * The CPU has been marked offline.  Migrate IRQs off this CPU.  If
 * the affinity settings do not allow other CPUs, force them onto any
 * available CPU.
 */
void migrate_irqs(void)
{
	unsigned int irq, cpu = smp_processor_id();

	for_each_active_irq(irq) {
		struct irq_data *data = irq_get_irq_data(irq);

		if (data->node == cpu) {
			unsigned int newcpu = cpumask_any_and(data->affinity,
							      cpu_online_mask);
			if (newcpu >= nr_cpu_ids) {
				if (printk_ratelimit())
					printk(KERN_INFO "IRQ%u no longer affine to CPU%u\n",
					       irq, cpu);

				cpumask_setall(data->affinity);
				newcpu = cpumask_any_and(data->affinity,
							 cpu_online_mask);
			}

			route_irq(data, irq, newcpu);
		}
	}
}
#endif
Commit	Line	Data
a6a31139	1	/*
1da177e4 LT	2	* linux/arch/sh/kernel/irq.c
	3	*
	4	* Copyright (C) 1992, 1998 Linus Torvalds, Ingo Molnar
	5	*
	6	*
	7	* SuperH version: Copyright (C) 1999 Niibe Yutaka
	8	*/
bf3a00f8	9	#include <linux/irq.h>
1da177e4	10	#include <linux/interrupt.h>
a6a31139	11	#include <linux/module.h>
bf3a00f8	12	#include <linux/kernel_stat.h>
1da177e4	13	#include <linux/seq_file.h>
ba93483f	14	#include <linux/ftrace.h>
763142d1	15	#include <linux/delay.h>
bf3a00f8	16	#include <asm/processor.h>
be782df5	17	#include <asm/machvec.h>
a6a31139 PM	18	#include <asm/uaccess.h>
a6a31139 PM	19	#include <asm/thread_info.h>
f15cbe6f	20	#include <cpu/mmu_context.h>
1da177e4	21
35f3c518 PM	22	atomic_t irq_err_count;
35f3c518 PM	23
1da177e4 LT	24	/*
	25	* 'what should we do if we get a hw irq event on an illegal vector'.
	26	* each architecture has to answer this themselves, it doesn't deserve
	27	* a generic callback i think.
	28	*/
	29	void ack_bad_irq(unsigned int irq)
	30	{
baf4326e	31	atomic_inc(&irq_err_count);
1da177e4 LT	32	printk("unexpected IRQ trap at vector %02x\n", irq);
	33	}
	34
	35	#if defined(CONFIG_PROC_FS)
fa1d43ab PM	36	/*
	37	* /proc/interrupts printing:
	38	*/
	39	static int show_other_interrupts(struct seq_file *p, int prec)
	40	{
731ba330 PM	41	int j;
	42
	43	seq_printf(p, "%*s: ", prec, "NMI");
	44	for_each_online_cpu(j)
	45	seq_printf(p, "%10u ", irq_stat[j].__nmi_count);
	46	seq_printf(p, " Non-maskable interrupts\n");
	47
fa1d43ab	48	seq_printf(p, "%*s: %10u\n", prec, "ERR", atomic_read(&irq_err_count));
731ba330	49
fa1d43ab PM	50	return 0;
	51	}
	52
1da177e4 LT	53	int show_interrupts(struct seq_file p, void v)
1da177e4 LT	54	{
fa1d43ab PM	55	unsigned long flags, any_count = 0;
	56	int i = (loff_t )v, j, prec;
	57	struct irqaction *action;
	58	struct irq_desc *desc;
faadfb04 PM	59	struct irq_data *data;
faadfb04 PM	60	struct irq_chip *chip;
fa1d43ab PM	61
	62	if (i > nr_irqs)
	63	return 0;
	64
	65	for (prec = 3, j = 1000; prec < 10 && j <= nr_irqs; ++prec)
	66	j *= 10;
	67
	68	if (i == nr_irqs)
	69	return show_other_interrupts(p, prec);
1da177e4 LT	70
1da177e4 LT	71	if (i == 0) {
fa1d43ab	72	seq_printf(p, "%*s", prec + 8, "");
394e3902	73	for_each_online_cpu(j)
fa1d43ab	74	seq_printf(p, "CPU%-8d", j);
1da177e4 LT	75	seq_putc(p, '\n');
	76	}
	77
fa1d43ab PM	78	desc = irq_to_desc(i);
	79	if (!desc)
	80	return 0;
	81
faadfb04 PM	82	data = irq_get_irq_data(i);
	83	chip = irq_data_get_irq_chip(data);
	84
239007b8	85	raw_spin_lock_irqsave(&desc->lock, flags);
fa1d43ab PM	86	for_each_online_cpu(j)
	87	any_count \|= kstat_irqs_cpu(i, j);
	88	action = desc->action;
	89	if (!action && !any_count)
	90	goto out;
1da177e4	91
fa1d43ab PM	92	seq_printf(p, "%*d: ", prec, i);
	93	for_each_online_cpu(j)
	94	seq_printf(p, "%10u ", kstat_irqs_cpu(i, j));
faadfb04	95	seq_printf(p, " %14s", chip->name);
fa1d43ab PM	96	seq_printf(p, "-%-8s", desc->name);
	97
	98	if (action) {
	99	seq_printf(p, " %s", action->name);
	100	while ((action = action->next) != NULL)
1da177e4	101	seq_printf(p, ", %s", action->name);
fa1d43ab	102	}
35f3c518	103
fa1d43ab PM	104	seq_putc(p, '\n');
fa1d43ab PM	105	out:
239007b8	106	raw_spin_unlock_irqrestore(&desc->lock, flags);
1da177e4 LT	107	return 0;
	108	}
	109	#endif
	110
110ed282	111	#ifdef CONFIG_IRQSTACKS
a6a31139 PM	112	/*
	113	* per-CPU IRQ handling contexts (thread information and stack)
	114	*/
	115	union irq_ctx {
	116	struct thread_info tinfo;
	117	u32 stack[THREAD_SIZE/sizeof(u32)];
	118	};
	119
1dc41e58 PM	120	static union irq_ctx *hardirq_ctx[NR_CPUS] __read_mostly;
1dc41e58 PM	121	static union irq_ctx *softirq_ctx[NR_CPUS] __read_mostly;
a6a31139	122
dc825b17 PM	123	static char softirq_stack[NR_CPUS * THREAD_SIZE] __page_aligned_bss;
	124	static char hardirq_stack[NR_CPUS * THREAD_SIZE] __page_aligned_bss;
	125
	126	static inline void handle_one_irq(unsigned int irq)
bf3a00f8	127	{
a6a31139	128	union irq_ctx curctx, irqctx;
a6a31139	129
a6a31139 PM	130	curctx = (union irq_ctx *)current_thread_info();
	131	irqctx = hardirq_ctx[smp_processor_id()];
	132
	133	/*
	134	* this is where we switch to the IRQ stack. However, if we are
	135	* already using the IRQ stack (because we interrupted a hardirq
	136	* handler) we can't do that and just have to keep using the
	137	* current stack (which is the irq stack already after all)
	138	*/
	139	if (curctx != irqctx) {
	140	u32 *isp;
	141
	142	isp = (u32 )((char )irqctx + sizeof(*irqctx));
	143	irqctx->tinfo.task = curctx->tinfo.task;
	144	irqctx->tinfo.previous_sp = current_stack_pointer;
	145
1dc41e58 PM	146	/*
	147	* Copy the softirq bits in preempt_count so that the
	148	* softirq checks work in the hardirq context.
	149	*/
	150	irqctx->tinfo.preempt_count =
	151	(irqctx->tinfo.preempt_count & ~SOFTIRQ_MASK) \|
	152	(curctx->tinfo.preempt_count & SOFTIRQ_MASK);
	153
a6a31139 PM	154	__asm__ __volatile__ (
a6a31139 PM	155	"mov %0, r4 \n"
1dc41e58	156	"mov r15, r8 \n"
baf4326e	157	"jsr @%1 \n"
a6a31139	158	/* swith to the irq stack */
baf4326e	159	" mov %2, r15 \n"
a6a31139	160	/* restore the stack (ring zero) */
1dc41e58	161	"mov r8, r15 \n"
a6a31139	162	: /* no outputs */
35f3c518	163	: "r" (irq), "r" (generic_handle_irq), "r" (isp)
a6a31139 PM	164	: "memory", "r0", "r1", "r2", "r3", "r4",
	165	"r5", "r6", "r7", "r8", "t", "pr"
	166	);
	167	} else
35f3c518	168	generic_handle_irq(irq);
1da177e4	169	}
a6a31139	170
a6a31139 PM	171	/*
	172	* allocate per-cpu stacks for hardirq and for softirq processing
	173	*/
	174	void irq_ctx_init(int cpu)
	175	{
	176	union irq_ctx *irqctx;
	177
	178	if (hardirq_ctx[cpu])
	179	return;
	180
	181	irqctx = (union irq_ctx )&hardirq_stack[cpu THREAD_SIZE];
	182	irqctx->tinfo.task = NULL;
	183	irqctx->tinfo.exec_domain = NULL;
	184	irqctx->tinfo.cpu = cpu;
	185	irqctx->tinfo.preempt_count = HARDIRQ_OFFSET;
	186	irqctx->tinfo.addr_limit = MAKE_MM_SEG(0);
	187
	188	hardirq_ctx[cpu] = irqctx;
	189
	190	irqctx = (union irq_ctx )&softirq_stack[cpu THREAD_SIZE];
	191	irqctx->tinfo.task = NULL;
	192	irqctx->tinfo.exec_domain = NULL;
	193	irqctx->tinfo.cpu = cpu;
1dc41e58	194	irqctx->tinfo.preempt_count = 0;
a6a31139 PM	195	irqctx->tinfo.addr_limit = MAKE_MM_SEG(0);
	196
	197	softirq_ctx[cpu] = irqctx;
	198
	199	printk("CPU %u irqstacks, hard=%p soft=%p\n",
	200	cpu, hardirq_ctx[cpu], softirq_ctx[cpu]);
	201	}
	202
	203	void irq_ctx_exit(int cpu)
	204	{
	205	hardirq_ctx[cpu] = NULL;
	206	}
	207
a6a31139 PM	208	asmlinkage void do_softirq(void)
	209	{
	210	unsigned long flags;
	211	struct thread_info *curctx;
	212	union irq_ctx *irqctx;
	213	u32 *isp;
	214
	215	if (in_interrupt())
	216	return;
	217
	218	local_irq_save(flags);
	219
	220	if (local_softirq_pending()) {
	221	curctx = current_thread_info();
	222	irqctx = softirq_ctx[smp_processor_id()];
	223	irqctx->tinfo.task = curctx->task;
	224	irqctx->tinfo.previous_sp = current_stack_pointer;
	225
	226	/* build the stack frame on the softirq stack */
	227	isp = (u32 )((char )irqctx + sizeof(*irqctx));
	228
	229	__asm__ __volatile__ (
	230	"mov r15, r9 \n"
	231	"jsr @%0 \n"
	232	/* switch to the softirq stack */
	233	" mov %1, r15 \n"
	234	/* restore the thread stack */
	235	"mov r9, r15 \n"
	236	: /* no outputs */
	237	: "r" (__do_softirq), "r" (isp)
a6a31139 PM	238	: "memory", "r0", "r1", "r2", "r3", "r4",
	239	"r5", "r6", "r7", "r8", "r9", "r15", "t", "pr"
	240	);
1dc41e58 PM	241
	242	/*
	243	* Shouldnt happen, we returned above if in_interrupt():
	244	*/
	245	WARN_ON_ONCE(softirq_count());
a6a31139 PM	246	}
	247
	248	local_irq_restore(flags);
	249	}
dc825b17 PM	250	#else
	251	static inline void handle_one_irq(unsigned int irq)
	252	{
	253	generic_handle_irq(irq);
	254	}
a6a31139	255	#endif
ea0f8fea	256
dc825b17 PM	257	asmlinkage __irq_entry int do_IRQ(unsigned int irq, struct pt_regs *regs)
	258	{
	259	struct pt_regs *old_regs = set_irq_regs(regs);
	260
	261	irq_enter();
	262
	263	irq = irq_demux(irq_lookup(irq));
	264
	265	if (irq != NO_IRQ_IGNORE) {
	266	handle_one_irq(irq);
	267	irq_finish(irq);
	268	}
	269
	270	irq_exit();
	271
	272	set_irq_regs(old_regs);
	273
	274	return IRQ_HANDLED;
	275	}
	276
ea0f8fea JL	277	void __init init_IRQ(void)
ea0f8fea JL	278	{
90015c89	279	plat_irq_setup();
ea0f8fea JL	280
	281	/* Perform the machine specific initialisation */
	282	if (sh_mv.mv_init_irq)
	283	sh_mv.mv_init_irq();
	284
c1e30ad9 PM	285	intc_finalize();
c1e30ad9 PM	286
ea0f8fea JL	287	irq_ctx_init(smp_processor_id());
ea0f8fea JL	288	}
d8586ba6 PM	289
	290	#ifdef CONFIG_SPARSE_IRQ
	291	int __init arch_probe_nr_irqs(void)
	292	{
	293	nr_irqs = sh_mv.mv_nr_irqs;
b683de2b	294	return NR_IRQS_LEGACY;
d8586ba6 PM	295	}
d8586ba6 PM	296	#endif
763142d1 PM	297
763142d1 PM	298	#ifdef CONFIG_HOTPLUG_CPU
fb41a49d	299	static void route_irq(struct irq_data *data, unsigned int irq, unsigned int cpu)
763142d1	300	{
fb41a49d PM	301	struct irq_desc *desc = irq_to_desc(irq);
	302	struct irq_chip *chip = irq_data_get_irq_chip(data);
	303
763142d1	304	printk(KERN_INFO "IRQ%u: moving from cpu%u to cpu%u\n",
fb41a49d	305	irq, data->node, cpu);
763142d1 PM	306
763142d1 PM	307	raw_spin_lock_irq(&desc->lock);
fb41a49d	308	chip->irq_set_affinity(data, cpumask_of(cpu), false);
763142d1 PM	309	raw_spin_unlock_irq(&desc->lock);
	310	}
	311
	312	/*
	313	* The CPU has been marked offline. Migrate IRQs off this CPU. If
	314	* the affinity settings do not allow other CPUs, force them onto any
	315	* available CPU.
	316	*/
	317	void migrate_irqs(void)
	318	{
763142d1 PM	319	unsigned int irq, cpu = smp_processor_id();
763142d1 PM	320
fb41a49d PM	321	for_each_active_irq(irq) {
	322	struct irq_data *data = irq_get_irq_data(irq);
	323
	324	if (data->node == cpu) {
	325	unsigned int newcpu = cpumask_any_and(data->affinity,
763142d1 PM	326	cpu_online_mask);
	327	if (newcpu >= nr_cpu_ids) {
	328	if (printk_ratelimit())
	329	printk(KERN_INFO "IRQ%u no longer affine to CPU%u\n",
	330	irq, cpu);
	331
fb41a49d PM	332	cpumask_setall(data->affinity);
fb41a49d PM	333	newcpu = cpumask_any_and(data->affinity,
763142d1 PM	334	cpu_online_mask);
	335	}
	336
fb41a49d	337	route_irq(data, irq, newcpu);
763142d1 PM	338	}
	339	}
	340	}
	341	#endif