/*
* 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/sched.h>
#include <linux/slab.h>
#include <linux/interrupt.h>
#include <linux/kernel_stat.h>
#include <asm/bootinfo.h>
#include <asm/irq.h>
#include <asm/lasat/lasatint.h>
#include <asm/gdb-stub.h>
static volatile int *lasat_int_status = NULL;
static volatile int *lasat_int_mask = NULL;
static volatile int lasat_int_mask_shift;
extern asmlinkage void lasatIRQ(void);
void disable_lasat_irq(unsigned int irq_nr)
{
unsigned long flags;
local_irq_save(flags);
*lasat_int_mask &= ~(1 << irq_nr) << lasat_int_mask_shift;
local_irq_restore(flags);
}
void enable_lasat_irq(unsigned int irq_nr)
{
unsigned long flags;
local_irq_save(flags);
*lasat_int_mask |= (1 << irq_nr) << lasat_int_mask_shift;
local_irq_restore(flags);
}
static unsigned int startup_lasat_irq(unsigned int irq)
{
enable_lasat_irq(irq);
return 0; /* never anything pending */
}
#define shutdown_lasat_irq disable_lasat_irq
#define mask_and_ack_lasat_irq disable_lasat_irq
static void end_lasat_irq(unsigned int irq)
{
if (!(irq_desc[irq].status & (IRQ_DISABLED|IRQ_INPROGRESS)))
enable_lasat_irq(irq);
}
static struct hw_interrupt_type lasat_irq_type = {
.typename = "Lasat",
.startup = startup_lasat_irq,
.shutdown = shutdown_lasat_irq,
.enable = enable_lasat_irq,
.disable = disable_lasat_irq,
.ack = mask_and_ack_lasat_irq,
.end = end_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;
}
void lasat_hw0_irqdispatch(struct pt_regs *regs)
{
unsigned long int_status;
int irq;
int_status = get_int_status();
/* if int_status == 0, then the interrupt has already been cleared */
if (int_status) {
irq = ls1bit32(int_status);
do_IRQ(irq, regs);
}
}
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");
}
/* Now safe to set the exception vector. */
set_except_vector(0, lasatIRQ);
for (i = 0; i <= LASATINT_END; i++) {
irq_desc[i].status = IRQ_DISABLED;
irq_desc[i].action = 0;
irq_desc[i].depth = 1;
irq_desc[i].handler = &lasat_irq_type;
}
}
