linux/arch/alpha/kernel/irq_srm.c

80 lines
1.6 KiB
C

/*
* Handle interrupts from the SRM, assuming no additional weirdness.
*/
#include <linux/init.h>
#include <linux/sched.h>
#include <linux/irq.h>
#include "proto.h"
#include "irq_impl.h"
/*
* Is the palcode SMP safe? In other words: can we call cserve_ena/dis
* at the same time in multiple CPUs? To be safe I added a spinlock
* but it can be removed trivially if the palcode is robust against smp.
*/
DEFINE_SPINLOCK(srm_irq_lock);
static inline void
srm_enable_irq(unsigned int irq)
{
spin_lock(&srm_irq_lock);
cserve_ena(irq - 16);
spin_unlock(&srm_irq_lock);
}
static void
srm_disable_irq(unsigned int irq)
{
spin_lock(&srm_irq_lock);
cserve_dis(irq - 16);
spin_unlock(&srm_irq_lock);
}
static unsigned int
srm_startup_irq(unsigned int irq)
{
srm_enable_irq(irq);
return 0;
}
static void
srm_end_irq(unsigned int irq)
{
if (!(irq_desc[irq].status & (IRQ_DISABLED|IRQ_INPROGRESS)))
srm_enable_irq(irq);
}
/* Handle interrupts from the SRM, assuming no additional weirdness. */
static struct hw_interrupt_type srm_irq_type = {
.typename = "SRM",
.startup = srm_startup_irq,
.shutdown = srm_disable_irq,
.enable = srm_enable_irq,
.disable = srm_disable_irq,
.ack = srm_disable_irq,
.end = srm_end_irq,
};
void __init
init_srm_irqs(long max, unsigned long ignore_mask)
{
long i;
for (i = 16; i < max; ++i) {
if (i < 64 && ((ignore_mask >> i) & 1))
continue;
irq_desc[i].status = IRQ_DISABLED | IRQ_LEVEL;
irq_desc[i].chip = &srm_irq_type;
}
}
void
srm_device_interrupt(unsigned long vector)
{
int irq = (vector - 0x800) >> 4;
handle_irq(irq);
}