Commit 354e6f72 authored by eric miao's avatar eric miao Committed by Russell King
Browse files

ARM: 6197/2: preliminary support for sparse IRQ 



So to allow NR_IRQS to be dynamic and platforms to specify the number
of IRQs really needed.

Acked-by: default avatarPaul Mundt <lethal@linux-sh.org>
Signed-off-by: default avatarEric Miao <eric.y.miao@gmail.com>
Signed-off-by: default avatarRussell King <rmk+kernel@arm.linux.org.uk>
parent 309caa9c

arch/arm/Kconfig

+12 −0
Original line number Diff line number Diff line
@@ -1289,6 +1289,18 @@ config HW_PERF_EVENTS 
	  Enable hardware performance counter support for perf events. If

	  disabled, perf events will use software events only.



config SPARSE_IRQ

	bool "Support sparse irq numbering"

	depends on EXPERIMENTAL

	help

	  This enables support for sparse irqs. This is useful in general

	  as most CPUs have a fairly sparse array of IRQ vectors, which

	  the irq_desc then maps directly on to. Systems with a high

	  number of off-chip IRQs will want to treat this as

	  experimental until they have been independently verified.



	  If you don't know what to do here, say N.



source "mm/Kconfig"



config LEDS

arch/arm/include/asm/irq.h

+2 −0
Original line number Diff line number Diff line
@@ -7,6 +7,8 @@ 
#define irq_canonicalize(i)	(i)

#endif



#define NR_IRQS_LEGACY	16



/*

 * Use this value to indicate lack of interrupt

 * capability

arch/arm/include/asm/mach/arch.h

+1 −0
Original line number Diff line number Diff line
@@ -20,6 +20,7 @@ struct machine_desc { 
	 * by assembler code in head.S, head-common.S

	 */

	unsigned int		nr;		/* architecture number	*/

	unsigned int		nr_irqs;	/* number of IRQs */

	unsigned int		phys_io;	/* start of physical io	*/

	unsigned int		io_pg_offst;	/* byte offset for io 

						 * page tabe entry	*/

arch/arm/include/asm/mach/irq.h

+1 −0
Original line number Diff line number Diff line
@@ -17,6 +17,7 @@ struct seq_file; 
/*

 * This is internal.  Do not use it.

 */

extern unsigned int arch_nr_irqs;

extern void (*init_arch_irq)(void);

extern void init_FIQ(void);

extern int show_fiq_list(struct seq_file *, void *);

arch/arm/kernel/irq.c

+27 −14
Original line number Diff line number Diff line
@@ -47,12 +47,14 @@ 
#define irq_finish(irq) do { } while (0)

#endif



unsigned int arch_nr_irqs;

void (*init_arch_irq)(void) __initdata = NULL;

unsigned long irq_err_count;



int show_interrupts(struct seq_file *p, void *v)

{

	int i = *(loff_t *) v, cpu;

	struct irq_desc *desc;

	struct irqaction * action;

	unsigned long flags;
@@ -67,24 +69,25 @@ int show_interrupts(struct seq_file *p, void *v) 
		seq_putc(p, '\n');

	}



	if (i < NR_IRQS) {

		raw_spin_lock_irqsave(&irq_desc[i].lock, flags);

		action = irq_desc[i].action;

	if (i < nr_irqs) {

		desc = irq_to_desc(i);

		raw_spin_lock_irqsave(&desc->lock, flags);

		action = desc->action;

		if (!action)

			goto unlock;



		seq_printf(p, "%3d: ", i);

		for_each_present_cpu(cpu)

			seq_printf(p, "%10u ", kstat_irqs_cpu(i, cpu));

		seq_printf(p, " %10s", irq_desc[i].chip->name ? : "-");

		seq_printf(p, " %10s", desc->chip->name ? : "-");

		seq_printf(p, "  %s", action->name);

		for (action = action->next; action; action = action->next)

			seq_printf(p, ", %s", action->name);



		seq_putc(p, '\n');

unlock:

		raw_spin_unlock_irqrestore(&irq_desc[i].lock, flags);

	} else if (i == NR_IRQS) {

		raw_spin_unlock_irqrestore(&desc->lock, flags);

	} else if (i == nr_irqs) {

#ifdef CONFIG_FIQ

		show_fiq_list(p, v);

#endif
@@ -112,7 +115,7 @@ asmlinkage void __exception asm_do_IRQ(unsigned int irq, struct pt_regs *regs) 
	 * Some hardware gives randomly wrong interrupts.  Rather

	 * than crashing, do something sensible.

	 */

	if (unlikely(irq >= NR_IRQS)) {

	if (unlikely(irq >= nr_irqs)) {

		if (printk_ratelimit())

			printk(KERN_WARNING "Bad IRQ%u\n", irq);

		ack_bad_irq(irq);
@@ -132,12 +135,12 @@ void set_irq_flags(unsigned int irq, unsigned int iflags) 
	struct irq_desc *desc;

	unsigned long flags;



	if (irq >= NR_IRQS) {

	if (irq >= nr_irqs) {

		printk(KERN_ERR "Trying to set irq flags for IRQ%d\n", irq);

		return;

	}



	desc = irq_desc + irq;

	desc = irq_to_desc(irq);

	raw_spin_lock_irqsave(&desc->lock, flags);

	desc->status |= IRQ_NOREQUEST | IRQ_NOPROBE | IRQ_NOAUTOEN;

	if (iflags & IRQF_VALID)
@@ -151,14 +154,25 @@ void set_irq_flags(unsigned int irq, unsigned int iflags) 


void __init init_IRQ(void)

{

	struct irq_desc *desc;

	int irq;



	for (irq = 0; irq < NR_IRQS; irq++)

		irq_desc[irq].status |= IRQ_NOREQUEST | IRQ_NOPROBE;

	for (irq = 0; irq < nr_irqs; irq++) {

		desc = irq_to_desc_alloc_node(irq, 0);

		desc->status |= IRQ_NOREQUEST | IRQ_NOPROBE;

	}



	init_arch_irq();

}



#ifdef CONFIG_SPARSE_IRQ

int __init arch_probe_nr_irqs(void)

{

	nr_irqs = arch_nr_irqs ? arch_nr_irqs : NR_IRQS;

	return 0;

}

#endif



#ifdef CONFIG_HOTPLUG_CPU



static void route_irq(struct irq_desc *desc, unsigned int irq, unsigned int cpu)
@@ -178,10 +192,9 @@ static void route_irq(struct irq_desc *desc, unsigned int irq, unsigned int cpu) 
void migrate_irqs(void)

{

	unsigned int i, cpu = smp_processor_id();

	struct irq_desc *desc;



	for (i = 0; i < NR_IRQS; i++) {

		struct irq_desc *desc = irq_desc + i;



	for_each_irq_desc(i, desc) {

		if (desc->node == cpu) {

			unsigned int newcpu = cpumask_any_and(desc->affinity,

							      cpu_online_mask);