irq.c
/*
* This program is free software; you can redistribute it and/or modify it
* under the terms of the GNU General Public License as published by the
* Free Software Foundation; either version 2 of the License, or (at your
* option) any later version.
*
* THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESS OR IMPLIED
* WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
* MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN
* NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
* INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
* NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF
* USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON
* ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
* (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
* THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*
* You should have received a copy of the GNU General Public License along
* with this program; if not, write to the Free Software Foundation, Inc.,
* 675 Mass Ave, Cambridge, MA 02139, USA.
*
* Copyright 2002 MontaVista Software Inc.
* Author: MontaVista Software, Inc.
* stevel@mvista.com or source@mvista.com
*/
#include <linux/bitops.h>
#include <linux/errno.h>
#include <linux/init.h>
#include <linux/io.h>
#include <linux/kernel_stat.h>
#include <linux/module.h>
#include <linux/signal.h>
#include <linux/sched.h>
#include <linux/types.h>
#include <linux/interrupt.h>
#include <linux/ioport.h>
#include <linux/timex.h>
#include <linux/random.h>
#include <linux/delay.h>
#include <asm/bootinfo.h>
#include <asm/time.h>
#include <asm/mipsregs.h>
#include <asm/mach-rc32434/irq.h>
#include <asm/mach-rc32434/gpio.h>
struct intr_group {
u32 mask; /* mask of valid bits in pending/mask registers */
volatile u32 *base_addr;
};
#define RC32434_NR_IRQS (GROUP4_IRQ_BASE + 32)
#if (NR_IRQS < RC32434_NR_IRQS)
#error Too little irqs defined. Did you override <asm/irq.h> ?
#endif
static const struct intr_group intr_group[NUM_INTR_GROUPS] = {
{
.mask = 0x0000efff,
.base_addr = (u32 *) KSEG1ADDR(IC_GROUP0_PEND + 0 * IC_GROUP_OFFSET)},
{
.mask = 0x00001fff,
.base_addr = (u32 *) KSEG1ADDR(IC_GROUP0_PEND + 1 * IC_GROUP_OFFSET)},
{
.mask = 0x00000007,
.base_addr = (u32 *) KSEG1ADDR(IC_GROUP0_PEND + 2 * IC_GROUP_OFFSET)},
{
.mask = 0x0003ffff,
.base_addr = (u32 *) KSEG1ADDR(IC_GROUP0_PEND + 3 * IC_GROUP_OFFSET)},
{
.mask = 0xffffffff,
.base_addr = (u32 *) KSEG1ADDR(IC_GROUP0_PEND + 4 * IC_GROUP_OFFSET)}
};
#define READ_PEND(base) (*(base))
#define READ_MASK(base) (*(base + 2))
#define WRITE_MASK(base, val) (*(base + 2) = (val))
static inline int irq_to_group(unsigned int irq_nr)
{
return (irq_nr - GROUP0_IRQ_BASE) >> 5;
}
static inline int group_to_ip(unsigned int group)
{
return group + 2;
}
static inline void enable_local_irq(unsigned int ip)
{
int ipnum = 0x100 << ip;
set_c0_status(ipnum);
}
static inline void disable_local_irq(unsigned int ip)
{
int ipnum = 0x100 << ip;
clear_c0_status(ipnum);
}
static inline void ack_local_irq(unsigned int ip)
{
int ipnum = 0x100 << ip;
clear_c0_cause(ipnum);
}
static void rb532_enable_irq(struct irq_data *d)
{
unsigned int group, intr_bit, irq_nr = d->irq;
int ip = irq_nr - GROUP0_IRQ_BASE;
volatile unsigned int *addr;
if (ip < 0)
enable_local_irq(irq_nr);
else {
group = ip >> 5;
ip &= (1 << 5) - 1;
intr_bit = 1 << ip;
enable_local_irq(group_to_ip(group));
addr = intr_group[group].base_addr;
WRITE_MASK(addr, READ_MASK(addr) & ~intr_bit);
}
}
static void rb532_disable_irq(struct irq_data *d)
{
unsigned int group, intr_bit, mask, irq_nr = d->irq;
int ip = irq_nr - GROUP0_IRQ_BASE;
volatile unsigned int *addr;
if (ip < 0) {
disable_local_irq(irq_nr);
} else {
group = ip >> 5;
ip &= (1 << 5) - 1;
intr_bit = 1 << ip;
addr = intr_group[group].base_addr;
mask = READ_MASK(addr);
mask |= intr_bit;
WRITE_MASK(addr, mask);
/* There is a maximum of 14 GPIO interrupts */
if (group == GPIO_MAPPED_IRQ_GROUP && irq_nr <= (GROUP4_IRQ_BASE + 13))
rb532_gpio_set_istat(0, irq_nr - GPIO_MAPPED_IRQ_BASE);
/*
* if there are no more interrupts enabled in this
* group, disable corresponding IP
*/
if (mask == intr_group[group].mask)
disable_local_irq(group_to_ip(group));
}
}
static void rb532_mask_and_ack_irq(struct irq_data *d)
{
rb532_disable_irq(d);
ack_local_irq(group_to_ip(irq_to_group(d->irq)));
}
static int rb532_set_type(struct irq_data *d, unsigned type)
{
int gpio = d->irq - GPIO_MAPPED_IRQ_BASE;
int group = irq_to_group(d->irq);
if (group != GPIO_MAPPED_IRQ_GROUP || d->irq > (GROUP4_IRQ_BASE + 13))
return (type == IRQ_TYPE_LEVEL_HIGH) ? 0 : -EINVAL;
switch (type) {
case IRQ_TYPE_LEVEL_HIGH:
rb532_gpio_set_ilevel(1, gpio);
break;
case IRQ_TYPE_LEVEL_LOW:
rb532_gpio_set_ilevel(0, gpio);
break;
default:
return -EINVAL;
}
return 0;
}
static struct irq_chip rc32434_irq_type = {
.name = "RB532",
.irq_ack = rb532_disable_irq,
.irq_mask = rb532_disable_irq,
.irq_mask_ack = rb532_mask_and_ack_irq,
.irq_unmask = rb532_enable_irq,
.irq_set_type = rb532_set_type,
};
void __init arch_init_irq(void)
{
int i;
pr_info("Initializing IRQ's: %d out of %d\n", RC32434_NR_IRQS, NR_IRQS);
for (i = 0; i < RC32434_NR_IRQS; i++)
irq_set_chip_and_handler(i, &rc32434_irq_type,
handle_level_irq);
}
/* Main Interrupt dispatcher */
asmlinkage void plat_irq_dispatch(void)
{
unsigned int ip, pend, group;
volatile unsigned int *addr;
unsigned int cp0_cause = read_c0_cause() & read_c0_status();
if (cp0_cause & CAUSEF_IP7) {
do_IRQ(7);
} else {
ip = (cp0_cause & 0x7c00);
if (ip) {
group = 21 + (fls(ip) - 32);
addr = intr_group[group].base_addr;
pend = READ_PEND(addr);
pend &= ~READ_MASK(addr); /* only unmasked interrupts */
pend = 39 + (fls(pend) - 32);
do_IRQ((group << 5) + pend);
}
}
}