kernel-ark/arch/arm/mach-ns9xxx/irq.c
Uwe Kleine-König 26c671c6b7 [ARM] 4493/1: ns9xxx: disable a non-reloading timer before ack'ing its irq
The HRM states that is must be done this way ...

Signed-off-by: Uwe Kleine-König <ukleinek@informatik.uni-freiburg.de>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2007-07-20 10:01:37 +01:00

104 lines
2.4 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 <asm/mach/irq.h>
#include <asm/mach-types.h>
#include <asm/arch-ns9xxx/regs-sys.h>
#include <asm/arch-ns9xxx/irqs.h>
#include <asm/arch-ns9xxx/board.h>
#include "generic.h"
static void ns9xxx_ack_irq_timer(unsigned int irq)
{
u32 tc = SYS_TC(irq - IRQ_TIMER0);
/*
* If the timer is programmed to halt on terminal count, the
* timer must be disabled before clearing the interrupt.
*/
if (REGGET(tc, SYS_TCx, REN) == 0) {
REGSET(tc, SYS_TCx, TEN, DIS);
SYS_TC(irq - IRQ_TIMER0) = tc;
}
REGSET(tc, SYS_TCx, INTC, SET);
SYS_TC(irq - IRQ_TIMER0) = tc;
REGSET(tc, SYS_TCx, INTC, UNSET);
SYS_TC(irq - IRQ_TIMER0) = tc;
}
static void (*ns9xxx_ack_irq_functions[NR_IRQS])(unsigned int) = {
[IRQ_TIMER0] = ns9xxx_ack_irq_timer,
[IRQ_TIMER1] = ns9xxx_ack_irq_timer,
[IRQ_TIMER2] = ns9xxx_ack_irq_timer,
[IRQ_TIMER3] = ns9xxx_ack_irq_timer,
};
static void ns9xxx_mask_irq(unsigned int irq)
{
/* XXX: better use cpp symbols */
SYS_IC(irq / 4) &= ~(1 << (7 + 8 * (3 - (irq & 3))));
}
static void ns9xxx_ack_irq(unsigned int irq)
{
if (!ns9xxx_ack_irq_functions[irq]) {
printk(KERN_ERR "no ack function for irq %u\n", irq);
BUG();
}
ns9xxx_ack_irq_functions[irq](irq);
SYS_ISRADDR = 0;
}
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 */
SYS_IC(irq / 4) |= 1 << (7 + 8 * (3 - (irq & 3)));
}
static struct irq_chip ns9xxx_chip = {
.ack = ns9xxx_ack_irq,
.mask = ns9xxx_mask_irq,
.mask_ack = ns9xxx_maskack_irq,
.unmask = ns9xxx_unmask_irq,
};
void __init ns9xxx_init_irq(void)
{
int i;
/* disable all IRQs */
for (i = 0; i < 8; ++i)
SYS_IC(i) = (4 * i) << 24 | (4 * i + 1) << 16 |
(4 * i + 2) << 8 | (4 * i + 3);
/* simple interrupt prio table:
* prio(x) < prio(y) <=> x < y
*/
for (i = 0; i < 32; ++i)
SYS_IVA(i) = i;
for (i = IRQ_WATCHDOG; i <= IRQ_EXT3; ++i) {
set_irq_chip(i, &ns9xxx_chip);
set_irq_handler(i, handle_level_irq);
set_irq_flags(i, IRQF_VALID);
}
}