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/*
* Code to handle DECstation IRQs plus some generic interrupt stuff.
*
* Copyright (C) 1992 Linus Torvalds
* Copyright (C) 1994, 1995, 1996, 1997, 2000 Ralf Baechle
*/
#include <linux/errno.h>
#include <linux/init.h>
#include <linux/kernel_stat.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/slab.h>
#include <linux/random.h>
#include <asm/bitops.h>
#include <asm/bootinfo.h>
#include <asm/io.h>
#include <asm/irq.h>
#include <asm/mipsregs.h>
#include <asm/system.h>
#include <asm/dec/interrupts.h>
extern void dec_init_kn01(void);
extern void dec_init_kn230(void);
extern void dec_init_kn02(void);
extern void dec_init_kn02ba(void);
extern void dec_init_kn02ca(void);
extern void dec_init_kn03(void);
extern asmlinkage void decstation_handle_int(void);
unsigned long spurious_count = 0;
static inline void mask_irq(unsigned int irq_nr)
{
unsigned int dummy;
if (dec_interrupt[irq_nr].iemask) { /* This is an ASIC interrupt */
*imr &= ~dec_interrupt[irq_nr].iemask;
dummy = *imr;
dummy = *imr;
} else /* This is a cpu interrupt */
change_cp0_status(ST0_IM, read_32bit_cp0_register(CP0_STATUS) & ~dec_interrupt[irq_nr].cpu_mask);
}
static inline void unmask_irq(unsigned int irq_nr)
{
unsigned int dummy;
if (dec_interrupt[irq_nr].iemask) { /* This is an ASIC interrupt */
*imr |= dec_interrupt[irq_nr].iemask;
dummy = *imr;
dummy = *imr;
}
change_cp0_status(ST0_IM, read_32bit_cp0_register(CP0_STATUS) | dec_interrupt[irq_nr].cpu_mask);
}
void disable_irq(unsigned int irq_nr)
{
unsigned long flags;
save_and_cli(flags);
mask_irq(irq_nr);
restore_flags(flags);
}
void enable_irq(unsigned int irq_nr)
{
unsigned long flags;
save_and_cli(flags);
unmask_irq(irq_nr);
restore_flags(flags);
}
/*
* Pointers to the low-level handlers: first the general ones, then the
* fast ones, then the bad ones.
*/
extern void interrupt(void);
static struct irqaction *irq_action[32] =
{
NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL,
NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL,
NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL,
NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL
};
int get_irq_list(char *buf)
{
int i, len = 0;
struct irqaction *action;
for (i = 0; i < 32; i++) {
action = irq_action[i];
if (!action)
continue;
len += sprintf(buf + len, "%2d: %8d %c %s",
i, kstat.irqs[0][i],
(action->flags & SA_INTERRUPT) ? '+' : ' ',
action->name);
for (action = action->next; action; action = action->next) {
len += sprintf(buf + len, ",%s %s",
(action->flags & SA_INTERRUPT) ? " +" : "",
action->name);
}
len += sprintf(buf + len, "\n");
}
return len;
}
/*
* do_IRQ handles IRQ's that have been installed without the
* SA_INTERRUPT flag: it uses the full signal-handling return
* and runs with other interrupts enabled. All relatively slow
* IRQ's should use this format: notably the keyboard/timer
* routines.
*/
asmlinkage void do_IRQ(int irq, struct pt_regs *regs)
{
struct irqaction *action;
int do_random, cpu;
cpu = smp_processor_id();
irq_enter(cpu, irq);
kstat.irqs[cpu][irq]++;
mask_irq(irq);
action = *(irq + irq_action);
if (action) {
if (!(action->flags & SA_INTERRUPT))
__sti();
action = *(irq + irq_action);
do_random = 0;
do {
do_random |= action->flags;
action->handler(irq, action->dev_id, regs);
action = action->next;
} while (action);
if (do_random & SA_SAMPLE_RANDOM)
add_interrupt_randomness(irq);
__cli();
unmask_irq(irq);
}
irq_exit(cpu, irq);
/* unmasking and bottom half handling is done magically for us. */
}
/*
* Idea is to put all interrupts
* in a single table and differenciate them just by number.
*/
int setup_dec_irq(int irq, struct irqaction *new)
{
int shared = 0;
struct irqaction *old, **p;
unsigned long flags;
p = irq_action + irq;
if ((old = *p) != NULL) {
/* Can't share interrupts unless both agree to */
if (!(old->flags & new->flags & SA_SHIRQ))
return -EBUSY;
/* Can't share interrupts unless both are same type */
if ((old->flags ^ new->flags) & SA_INTERRUPT)
return -EBUSY;
/* add new interrupt at end of irq queue */
do {
p = &old->next;
old = *p;
} while (old);
shared = 1;
}
if (new->flags & SA_SAMPLE_RANDOM)
rand_initialize_irq(irq);
save_and_cli(flags);
*p = new;
if (!shared) {
unmask_irq(irq);
}
restore_flags(flags);
return 0;
}
int request_irq(unsigned int irq,
void (*handler) (int, void *, struct pt_regs *),
unsigned long irqflags,
const char *devname,
void *dev_id)
{
int retval;
struct irqaction *action;
if (irq >= 32)
return -EINVAL;
if (!handler)
return -EINVAL;
action = (struct irqaction *) kmalloc(sizeof(struct irqaction), GFP_KERNEL);
if (!action)
return -ENOMEM;
action->handler = handler;
action->flags = irqflags;
action->mask = 0;
action->name = devname;
action->next = NULL;
action->dev_id = dev_id;
retval = setup_dec_irq(irq, action);
if (retval)
kfree(action);
return retval;
}
void free_irq(unsigned int irq, void *dev_id)
{
struct irqaction *action, **p;
unsigned long flags;
if (irq > 39) {
printk("Trying to free IRQ%d\n", irq);
return;
}
for (p = irq + irq_action; (action = *p) != NULL; p = &action->next) {
if (action->dev_id != dev_id)
continue;
/* Found it - now free it */
save_and_cli(flags);
*p = action->next;
if (!irq[irq_action])
mask_irq(irq);
restore_flags(flags);
kfree(action);
return;
}
printk("Trying to free free IRQ%d\n", irq);
}
unsigned long probe_irq_on(void)
{
/* TODO */
return 0;
}
int probe_irq_off(unsigned long irqs)
{
/* TODO */
return 0;
}
void __init init_IRQ(void)
{
switch (mips_machtype) {
case MACH_DS23100:
dec_init_kn01();
break;
case MACH_DS5100: /* DS5100 MIPSMATE */
dec_init_kn230();
break;
case MACH_DS5000_200: /* DS5000 3max */
dec_init_kn02();
break;
case MACH_DS5000_1XX: /* DS5000/100 3min */
dec_init_kn02ba();
break;
case MACH_DS5000_2X0: /* DS5000/240 3max+ */
dec_init_kn03();
break;
case MACH_DS5000_XX: /* Personal DS5000/2x */
dec_init_kn02ca();
break;
case MACH_DS5800: /* DS5800 Isis */
panic("Don't know how to set this up!");
break;
case MACH_DS5400: /* DS5400 MIPSfair */
panic("Don't know how to set this up!");
break;
case MACH_DS5500: /* DS5500 MIPSfair-2 */
panic("Don't know how to set this up!");
break;
}
set_except_vector(0, decstation_handle_int);
}
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