arm64: IRQ handling

/*

 * Copyright (C) 2012 ARM Ltd.

 *

 * This program is free software; you can redistribute it and/or modify

 * it under the terms of the GNU General Public License version 2 as

 * published by the Free Software Foundation.

 *

 * This program is distributed in the hope that it will be useful,

 * but WITHOUT ANY WARRANTY; without even the implied warranty of

 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the

 * GNU General Public License for more details.

 *

 * You should have received a copy of the GNU General Public License

 * along with this program.  If not, see <http://www.gnu.org/licenses/>.

 */

#ifndef __ASM_HARDIRQ_H

#define __ASM_HARDIRQ_H

#include <linux/cache.h>

#include <linux/threads.h>

#include <asm/irq.h>

typedef struct {

	unsigned int __softirq_pending;

} ____cacheline_aligned irq_cpustat_t;

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

#define __inc_irq_stat(cpu, member)	__IRQ_STAT(cpu, member)++

#define __get_irq_stat(cpu, member)	__IRQ_STAT(cpu, member)

#ifdef CONFIG_SMP

u64 smp_irq_stat_cpu(unsigned int cpu);

#define arch_irq_stat_cpu	smp_irq_stat_cpu

#endif

#define __ARCH_IRQ_EXIT_IRQS_DISABLED	1

static inline void ack_bad_irq(unsigned int irq)

{

	extern unsigned long irq_err_count;

	irq_err_count++;

}

extern void handle_IRQ(unsigned int, struct pt_regs *);

#endif /* __ASM_HARDIRQ_H */

#ifndef __ASM_IRQ_H

#define __ASM_IRQ_H

#include <asm-generic/irq.h>

extern void (*handle_arch_irq)(struct pt_regs *);

#endif

/*

 * Copyright (C) 2012 ARM Ltd.

 *

 * This program is free software; you can redistribute it and/or modify

 * it under the terms of the GNU General Public License version 2 as

 * published by the Free Software Foundation.

 *

 * This program is distributed in the hope that it will be useful,

 * but WITHOUT ANY WARRANTY; without even the implied warranty of

 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the

 * GNU General Public License for more details.

 *

 * You should have received a copy of the GNU General Public License

 * along with this program.  If not, see <http://www.gnu.org/licenses/>.

 */

#ifndef __ASM_IRQFLAGS_H

#define __ASM_IRQFLAGS_H

#ifdef __KERNEL__

#include <asm/ptrace.h>

/*

 * CPU interrupt mask handling.

 */

static inline unsigned long arch_local_irq_save(void)

{

	unsigned long flags;

	asm volatile(

		"mrs	%0, daif		// arch_local_irq_save\n"

		"msr	daifset, #2"

		: "=r" (flags)

		:

		: "memory");

	return flags;

}

static inline void arch_local_irq_enable(void)

{

	asm volatile(

		"msr	daifclr, #2		// arch_local_irq_enable"

		:

		:

		: "memory");

}

static inline void arch_local_irq_disable(void)

{

	asm volatile(

		"msr	daifset, #2		// arch_local_irq_disable"

		:

		:

		: "memory");

}

#define local_fiq_enable()	asm("msr	daifclr, #1" : : : "memory")

#define local_fiq_disable()	asm("msr	daifset, #1" : : : "memory")

/*

 * Save the current interrupt enable state.

 */

static inline unsigned long arch_local_save_flags(void)

{

	unsigned long flags;

	asm volatile(

		"mrs	%0, daif		// arch_local_save_flags"

		: "=r" (flags)

		:

		: "memory");

	return flags;

}

/*

 * restore saved IRQ state

 */

static inline void arch_local_irq_restore(unsigned long flags)

{

	asm volatile(

		"msr	daif, %0		// arch_local_irq_restore"

	:

	: "r" (flags)

	: "memory");

}

static inline int arch_irqs_disabled_flags(unsigned long flags)

{

	return flags & PSR_I_BIT;

}

#endif

#endif

/*

 * Based on arch/arm/kernel/irq.c

 *

 * Copyright (C) 1992 Linus Torvalds

 * Modifications for ARM processor Copyright (C) 1995-2000 Russell King.

 * Support for Dynamic Tick Timer Copyright (C) 2004-2005 Nokia Corporation.

 * Dynamic Tick Timer written by Tony Lindgren <tony@atomide.com> and

 * Tuukka Tikkanen <tuukka.tikkanen@elektrobit.com>.

 * Copyright (C) 2012 ARM Ltd.

 *

 * This program is free software; you can redistribute it and/or modify

 * it under the terms of the GNU General Public License version 2 as

 * published by the Free Software Foundation.

 *

 * This program is distributed in the hope that it will be useful,

 * but WITHOUT ANY WARRANTY; without even the implied warranty of

 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the

 * GNU General Public License for more details.

 *

 * You should have received a copy of the GNU General Public License

 * along with this program.  If not, see <http://www.gnu.org/licenses/>.

 */

#include <linux/kernel_stat.h>

#include <linux/irq.h>

#include <linux/smp.h>

#include <linux/init.h>

#include <linux/of_irq.h>

#include <linux/seq_file.h>

#include <linux/ratelimit.h>

unsigned long irq_err_count;

int arch_show_interrupts(struct seq_file *p, int prec)

{

#ifdef CONFIG_SMP

	show_ipi_list(p, prec);

#endif

	seq_printf(p, "%*s: %10lu\n", prec, "Err", irq_err_count);

	return 0;

}

/*

 * handle_IRQ handles all hardware IRQ's.  Decoded IRQs should

 * not come via this function.  Instead, they should provide their

 * own 'handler'.  Used by platform code implementing C-based 1st

 * level decoding.

 */

void handle_IRQ(unsigned int irq, struct pt_regs *regs)

{

	struct pt_regs *old_regs = set_irq_regs(regs);

	irq_enter();

	/*

	 * Some hardware gives randomly wrong interrupts.  Rather

	 * than crashing, do something sensible.

	 */

	if (unlikely(irq >= nr_irqs)) {

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

		ack_bad_irq(irq);

	} else {

		generic_handle_irq(irq);

	}

	irq_exit();

	set_irq_regs(old_regs);

}

/*

 * Interrupt controllers supported by the kernel.

 */

static const struct of_device_id intctrl_of_match[] __initconst = {

	/* IRQ controllers { .compatible, .data } info to go here */

	{}

};

void __init init_IRQ(void)

{

	of_irq_init(intctrl_of_match);

	if (!handle_arch_irq)

		panic("No interrupt controller found.");

}