/*
* Carsten Langgaard, carstenl@mips.com
* Copyright (C) 1999,2000 MIPS Technologies, Inc. All rights reserved.
*
* This program is free software; you can distribute 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 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, write to the Free Software Foundation, Inc.,
* 59 Temple Place - Suite 330, Boston MA 02111-1307, USA.
*
* Routines for generic manipulation of the interrupts found on the
* Lasat boards.
*/
#include <linux/init.h>
#include <linux/interrupt.h>
#include <linux/irq.h>
#include <asm/bootinfo.h>
#include <asm/irq_cpu.h>
#include <asm/lasat/lasatint.h>
#include <irq.h>
static volatile int *lasat_int_status;
static volatile int *lasat_int_mask;
static volatile int lasat_int_mask_shift;
void disable_lasat_irq(unsigned int irq_nr)
{
irq_nr -= LASAT_IRQ_BASE;
*lasat_int_mask &= ~(1 << irq_nr) << lasat_int_mask_shift;
}
void enable_lasat_irq(unsigned int irq_nr)
{
irq_nr -= LASAT_IRQ_BASE;
*lasat_int_mask |= (1 << irq_nr) << lasat_int_mask_shift;
}
static struct irq_chip lasat_irq_type = {
.name = "Lasat",
.ack = disable_lasat_irq,
.mask = disable_lasat_irq,
.mask_ack = disable_lasat_irq,
.unmask = enable_lasat_irq,
};
static inline int ls1bit32(unsigned int x)
{
int b = 31, s;
s = 16; if (x << 16 == 0) s = 0; b -= s; x <<= s;
s = 8; if (x << 8 == 0) s = 0; b -= s; x <<= s;
s = 4; if (x << 4 == 0) s = 0; b -= s; x <<= s;
s = 2; if (x << 2 == 0) s = 0; b -= s; x <<= s;
s = 1; if (x << 1 == 0) s = 0; b -= s;
return b;
}
static unsigned long (*get_int_status)(void);
static unsigned long get_int_status_100(void)
{
return *lasat_int_status & *lasat_int_mask;
}
static unsigned long get_int_status_200(void)
{
unsigned long int_status;
int_status = *lasat_int_status;
int_status &= (int_status >> LASATINT_MASK_SHIFT_200) & 0xffff;
return int_status;
}
asmlinkage void plat_irq_dispatch(void)
{
unsigned long int_status;
unsigned int cause = read_c0_cause();
int irq;
if (cause & CAUSEF_IP7) { /* R4000 count / compare IRQ */
do_IRQ(7);
return;
}
int_status = get_int_status();
/* if int_status == 0, then the interrupt has already been cleared */
if (int_status) {
irq = LASAT_IRQ_BASE + ls1bit32(int_status);
do_IRQ(irq);
}
}
static struct irqaction cascade = {
.handler = no_action,
.mask = CPU_MASK_NONE,
.name = "cascade",
};
void __init arch_init_irq(void)
{
int i;
switch (mips_machtype) {
case MACH_LASAT_100:
lasat_int_status = (void *)LASAT_INT_STATUS_REG_100;
lasat_int_mask = (void *)LASAT_INT_MASK_REG_100;
lasat_int_mask_shift = LASATINT_MASK_SHIFT_100;
get_int_status = get_int_status_100;
*lasat_int_mask = 0;
break;
case MACH_LASAT_200:
lasat_int_status = (void *)LASAT_INT_STATUS_REG_200;
lasat_int_mask = (void *)LASAT_INT_MASK_REG_200;
lasat_int_mask_shift = LASATINT_MASK_SHIFT_200;
get_int_status = get_int_status_200;
*lasat_int_mask &= 0xffff;
break;
default:
panic("arch_init_irq: mips_machtype incorrect");
}
mips_cpu_irq_init();
for (i = LASAT_IRQ_BASE; i <= LASAT_IRQ_END; i++)
set_irq_chip_and_handler(i, &lasat_irq_type, handle_level_irq);
setup_irq(LASAT_CASCADE_IRQ, &cascade);
}
