[deliverable/linux.git] / arch / s390 / kernel / irq.c

/*
 *  arch/s390/kernel/irq.c
 *
 *    Copyright IBM Corp. 2004,2007
 *    Author(s): Martin Schwidefsky (schwidefsky@de.ibm.com),
 *		 Thomas Spatzier (tspat@de.ibm.com)
 *
 * This file contains interrupt related functions.
 */

#include <linux/module.h>
#include <linux/kernel.h>
#include <linux/kernel_stat.h>
#include <linux/interrupt.h>
#include <linux/seq_file.h>
#include <linux/cpu.h>
#include <linux/proc_fs.h>
#include <linux/profile.h>

int nr_irqs = NR_IRQS;
EXPORT_SYMBOL(nr_irqs);

/*
 * show_interrupts is needed by /proc/interrupts.
 */
int show_interrupts(struct seq_file *p, void *v)
{
	static const char *intrclass_names[] = { "EXT", "I/O", };
	int i = *(loff_t *) v, j;

	get_online_cpus();
	if (i == 0) {
		seq_puts(p, "           ");
		for_each_online_cpu(j)
			seq_printf(p, "CPU%d       ",j);
		seq_putc(p, '\n');
	}

	if (i < NR_IRQS) {
		seq_printf(p, "%s: ", intrclass_names[i]);
#ifndef CONFIG_SMP
		seq_printf(p, "%10u ", kstat_irqs(i));
#else
		for_each_online_cpu(j)
			seq_printf(p, "%10u ", kstat_cpu(j).irqs[i]);
#endif
                seq_putc(p, '\n');

        }
	put_online_cpus();
        return 0;
}

/*
 * For compatibilty only. S/390 specific setup of interrupts et al. is done
 * much later in init_channel_subsystem().
 */
void __init
init_IRQ(void)
{
	/* nothing... */
}

/*
 * Switch to the asynchronous interrupt stack for softirq execution.
 */
asmlinkage void do_softirq(void)
{
	unsigned long flags, old, new;

	if (in_interrupt())
		return;

	local_irq_save(flags);

	if (local_softirq_pending()) {
		/* Get current stack pointer. */
		asm volatile("la %0,0(15)" : "=a" (old));
		/* Check against async. stack address range. */
		new = S390_lowcore.async_stack;
		if (((new - old) >> (PAGE_SHIFT + THREAD_ORDER)) != 0) {
			/* Need to switch to the async. stack. */
			new -= STACK_FRAME_OVERHEAD;
			((struct stack_frame *) new)->back_chain = old;

			asm volatile("   la    15,0(%0)\n"
				     "   basr  14,%2\n"
				     "   la    15,0(%1)\n"
				     : : "a" (new), "a" (old),
				         "a" (__do_softirq)
				     : "0", "1", "2", "3", "4", "5", "14",
				       "cc", "memory" );
		} else
			/* We are already on the async stack. */
			__do_softirq();
	}

	local_irq_restore(flags);
}

void init_irq_proc(void)
{
	struct proc_dir_entry *root_irq_dir;

	root_irq_dir = proc_mkdir("irq", NULL);
	create_prof_cpu_mask(root_irq_dir);
}
Commit	Line	Data
1da177e4 LT	1	/*
	2	* arch/s390/kernel/irq.c
	3	*
55dff522	4	* Copyright IBM Corp. 2004,2007
1da177e4	5	* Author(s): Martin Schwidefsky (schwidefsky@de.ibm.com),
55dff522	6	* Thomas Spatzier (tspat@de.ibm.com)
1da177e4 LT	7	*
	8	* This file contains interrupt related functions.
	9	*/
	10
	11	#include <linux/module.h>
	12	#include <linux/kernel.h>
	13	#include <linux/kernel_stat.h>
	14	#include <linux/interrupt.h>
	15	#include <linux/seq_file.h>
	16	#include <linux/cpu.h>
55dff522 HC	17	#include <linux/proc_fs.h>
55dff522 HC	18	#include <linux/profile.h>
1da177e4	19
85c0f909	20	int nr_irqs = NR_IRQS;
c59d85a7	21	EXPORT_SYMBOL(nr_irqs);
85c0f909	22
1da177e4 LT	23	/*
	24	* show_interrupts is needed by /proc/interrupts.
	25	*/
	26	int show_interrupts(struct seq_file p, void v)
	27	{
	28	static const char *intrclass_names[] = { "EXT", "I/O", };
	29	int i = (loff_t ) v, j;
	30
8dd79cb1	31	get_online_cpus();
1da177e4 LT	32	if (i == 0) {
	33	seq_puts(p, " ");
	34	for_each_online_cpu(j)
	35	seq_printf(p, "CPU%d ",j);
	36	seq_putc(p, '\n');
	37	}
	38
	39	if (i < NR_IRQS) {
	40	seq_printf(p, "%s: ", intrclass_names[i]);
	41	#ifndef CONFIG_SMP
	42	seq_printf(p, "%10u ", kstat_irqs(i));
	43	#else
	44	for_each_online_cpu(j)
	45	seq_printf(p, "%10u ", kstat_cpu(j).irqs[i]);
	46	#endif
	47	seq_putc(p, '\n');
	48
	49	}
8dd79cb1	50	put_online_cpus();
1da177e4 LT	51	return 0;
	52	}
	53
	54	/*
	55	* For compatibilty only. S/390 specific setup of interrupts et al. is done
	56	* much later in init_channel_subsystem().
	57	*/
	58	void __init
	59	init_IRQ(void)
	60	{
	61	/* nothing... */
	62	}
	63
	64	/*
	65	* Switch to the asynchronous interrupt stack for softirq execution.
	66	*/
1da177e4 LT	67	asmlinkage void do_softirq(void)
	68	{
	69	unsigned long flags, old, new;
	70
	71	if (in_interrupt())
	72	return;
	73
	74	local_irq_save(flags);
	75
1da177e4 LT	76	if (local_softirq_pending()) {
	77	/* Get current stack pointer. */
	78	asm volatile("la %0,0(15)" : "=a" (old));
	79	/* Check against async. stack address range. */
	80	new = S390_lowcore.async_stack;
	81	if (((new - old) >> (PAGE_SHIFT + THREAD_ORDER)) != 0) {
	82	/* Need to switch to the async. stack. */
	83	new -= STACK_FRAME_OVERHEAD;
	84	((struct stack_frame *) new)->back_chain = old;
	85
	86	asm volatile(" la 15,0(%0)\n"
	87	" basr 14,%2\n"
	88	" la 15,0(%1)\n"
	89	: : "a" (new), "a" (old),
	90	"a" (__do_softirq)
	91	: "0", "1", "2", "3", "4", "5", "14",
	92	"cc", "memory" );
	93	} else
	94	/* We are already on the async stack. */
	95	__do_softirq();
	96	}
	97
1da177e4 LT	98	local_irq_restore(flags);
1da177e4 LT	99	}
55dff522 HC	100
	101	void init_irq_proc(void)
	102	{
	103	struct proc_dir_entry *root_irq_dir;
	104
	105	root_irq_dir = proc_mkdir("irq", NULL);
	106	create_prof_cpu_mask(root_irq_dir);
	107	}