linux-stable-rt/arch/arm/mach-ns9xxx/irq.c

126 lines
2.8 KiB
C

/*
* arch/arm/mach-ns9xxx/irq.c
*
* Copyright (C) 2006,2007 by Digi International Inc.
* All rights reserved.
*
* 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.
*/
#include <linux/interrupt.h>
#include <linux/kernel_stat.h>
#include <linux/io.h>
#include <asm/mach/irq.h>
#include <mach/regs-sys-common.h>
#include <mach/irqs.h>
#include <mach/board.h>
#include "generic.h"
/* simple interrupt prio table: prio(x) < prio(y) <=> x < y */
#define irq2prio(i) (i)
#define prio2irq(p) (p)
static void ns9xxx_mask_irq(unsigned int irq)
{
/* XXX: better use cpp symbols */
int prio = irq2prio(irq);
u32 ic = __raw_readl(SYS_IC(prio / 4));
ic &= ~(1 << (7 + 8 * (3 - (prio & 3))));
__raw_writel(ic, SYS_IC(prio / 4));
}
static void ns9xxx_ack_irq(unsigned int irq)
{
__raw_writel(0, SYS_ISRADDR);
}
static void ns9xxx_maskack_irq(unsigned int irq)
{
ns9xxx_mask_irq(irq);
ns9xxx_ack_irq(irq);
}
static void ns9xxx_unmask_irq(unsigned int irq)
{
/* XXX: better use cpp symbols */
int prio = irq2prio(irq);
u32 ic = __raw_readl(SYS_IC(prio / 4));
ic |= 1 << (7 + 8 * (3 - (prio & 3)));
__raw_writel(ic, SYS_IC(prio / 4));
}
static struct irq_chip ns9xxx_chip = {
.ack = ns9xxx_ack_irq,
.mask = ns9xxx_mask_irq,
.mask_ack = ns9xxx_maskack_irq,
.unmask = ns9xxx_unmask_irq,
};
#if 0
#define handle_irq handle_level_irq
#else
static void handle_prio_irq(unsigned int irq, struct irq_desc *desc)
{
struct irqaction *action;
irqreturn_t action_ret;
spin_lock(&desc->lock);
BUG_ON(desc->status & IRQ_INPROGRESS);
desc->status &= ~(IRQ_REPLAY | IRQ_WAITING);
kstat_incr_irqs_this_cpu(irq, desc);
action = desc->action;
if (unlikely(!action || (desc->status & IRQ_DISABLED)))
goto out_mask;
desc->status |= IRQ_INPROGRESS;
spin_unlock(&desc->lock);
action_ret = handle_IRQ_event(irq, action);
/* XXX: There is no direct way to access noirqdebug, so check
* unconditionally for spurious irqs...
* Maybe this function should go to kernel/irq/chip.c? */
note_interrupt(irq, desc, action_ret);
spin_lock(&desc->lock);
desc->status &= ~IRQ_INPROGRESS;
if (desc->status & IRQ_DISABLED)
out_mask:
desc->chip->mask(irq);
/* ack unconditionally to unmask lower prio irqs */
desc->chip->ack(irq);
spin_unlock(&desc->lock);
}
#define handle_irq handle_prio_irq
#endif
void __init ns9xxx_init_irq(void)
{
int i;
/* disable all IRQs */
for (i = 0; i < 8; ++i)
__raw_writel(prio2irq(4 * i) << 24 |
prio2irq(4 * i + 1) << 16 |
prio2irq(4 * i + 2) << 8 |
prio2irq(4 * i + 3),
SYS_IC(i));
for (i = 0; i < 32; ++i)
__raw_writel(prio2irq(i), SYS_IVA(i));
for (i = 0; i <= 31; ++i) {
set_irq_chip(i, &ns9xxx_chip);
set_irq_handler(i, handle_irq);
set_irq_flags(i, IRQF_VALID);
}
}