linux/arch/arm/plat-samsung/irq-vic-timer.c

87 lines
2.3 KiB
C

/* arch/arm/plat-samsung/irq-vic-timer.c
* originally part of arch/arm/plat-s3c64xx/irq.c
*
* Copyright 2008 Openmoko, Inc.
* Copyright 2008 Simtec Electronics
* Ben Dooks <ben@simtec.co.uk>
* http://armlinux.simtec.co.uk/
*
* S3C64XX - Interrupt handling
*
* 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/kernel.h>
#include <linux/interrupt.h>
#include <linux/irq.h>
#include <linux/io.h>
#include <mach/map.h>
#include <plat/irq-vic-timer.h>
#include <plat/regs-timer.h>
static void s3c_irq_demux_vic_timer(unsigned int irq, struct irq_desc *desc)
{
generic_handle_irq((int)desc->handler_data);
}
/* We assume the IRQ_TIMER0..IRQ_TIMER4 range is continuous. */
static void s3c_irq_timer_mask(unsigned int irq)
{
u32 reg = __raw_readl(S3C64XX_TINT_CSTAT);
reg &= 0x1f; /* mask out pending interrupts */
reg &= ~(1 << (irq - IRQ_TIMER0));
__raw_writel(reg, S3C64XX_TINT_CSTAT);
}
static void s3c_irq_timer_unmask(unsigned int irq)
{
u32 reg = __raw_readl(S3C64XX_TINT_CSTAT);
reg &= 0x1f; /* mask out pending interrupts */
reg |= 1 << (irq - IRQ_TIMER0);
__raw_writel(reg, S3C64XX_TINT_CSTAT);
}
static void s3c_irq_timer_ack(unsigned int irq)
{
u32 reg = __raw_readl(S3C64XX_TINT_CSTAT);
reg &= 0x1f;
reg |= (1 << 5) << (irq - IRQ_TIMER0);
__raw_writel(reg, S3C64XX_TINT_CSTAT);
}
static struct irq_chip s3c_irq_timer = {
.name = "s3c-timer",
.mask = s3c_irq_timer_mask,
.unmask = s3c_irq_timer_unmask,
.ack = s3c_irq_timer_ack,
};
/**
* s3c_init_vic_timer_irq() - initialise timer irq chanined off VIC.\
* @parent_irq: The parent IRQ on the VIC for the timer.
* @timer_irq: The IRQ to be used for the timer.
*
* Register the necessary IRQ chaining and support for the timer IRQs
* chained of the VIC.
*/
void __init s3c_init_vic_timer_irq(unsigned int parent_irq,
unsigned int timer_irq)
{
struct irq_desc *desc = irq_to_desc(parent_irq);
set_irq_chained_handler(parent_irq, s3c_irq_demux_vic_timer);
set_irq_chip(timer_irq, &s3c_irq_timer);
set_irq_handler(timer_irq, handle_level_irq);
set_irq_flags(timer_irq, IRQF_VALID);
desc->handler_data = (void *)timer_irq;
}