/*
* This function emulates a interrupt processing when a cpu is about to be
* brought down.
*/
void ia64_process_pending_intr(void)
{
ia64_vector vector;
unsigned long saved_tpr;
extern unsigned int vectors_in_migration[NR_IRQS];
vector = ia64_get_ivr();
irq_enter();
saved_tpr = ia64_getreg(_IA64_REG_CR_TPR);
ia64_srlz_d();
/*
* Perform normal interrupt style processing
*/
while (vector != IA64_SPURIOUS_INT_VECTOR) {
int irq = local_vector_to_irq(vector);
if (unlikely(IS_LOCAL_TLB_FLUSH(vector))) {
smp_local_flush_tlb();
kstat_incr_irq_this_cpu(irq);
} else if (unlikely(IS_RESCHEDULE(vector))) {
kstat_incr_irq_this_cpu(irq);
} else {
struct pt_regs *old_regs = set_irq_regs(NULL);
ia64_setreg(_IA64_REG_CR_TPR, vector);
ia64_srlz_d();
/*
* Now try calling normal ia64_handle_irq as it would have got called
* from a real intr handler. Try passing null for pt_regs, hopefully
* it will work. I hope it works!.
* Probably could shared code.
*/
if (unlikely(irq < 0)) {
printk(KERN_ERR "%s: Unexpected interrupt "
"vector %d on CPU %d not being mapped "
"to any IRQ!!\n", __func__, vector,
smp_processor_id());
} else {
vectors_in_migration[irq]=0;
generic_handle_irq(irq);
}
set_irq_regs(old_regs);
/*
* Disable interrupts and send EOI
*/
local_irq_disable();
ia64_setreg(_IA64_REG_CR_TPR, saved_tpr);
}
ia64_eoi();
vector = ia64_get_ivr();
}
irq_exit();
}
/*
* Use cio_tsch to update the subchannel status and call the interrupt handler
* if status had been pending. Called with the subchannel's lock held.
*/
void cio_tsch(struct subchannel *sch)
{
struct irb *irb;
int irq_context;
irb = this_cpu_ptr(&cio_irb);
/* Store interrupt response block to lowcore. */
if (tsch(sch->schid, irb) != 0)
/* Not status pending or not operational. */
return;
memcpy(&sch->schib.scsw, &irb->scsw, sizeof(union scsw));
/* Call interrupt handler with updated status. */
irq_context = in_interrupt();
if (!irq_context) {
local_bh_disable();
irq_enter();
}
kstat_incr_irq_this_cpu(IO_INTERRUPT);
if (sch->driver && sch->driver->irq)
sch->driver->irq(sch);
else
inc_irq_stat(IRQIO_CIO);
if (!irq_context) {
irq_exit();
_local_bh_enable();
}
}
/*
* That's where the IVT branches when we get an external
* interrupt. This branches to the correct hardware IRQ handler via
* function ptr.
*/
void
ia64_handle_irq (ia64_vector vector, struct pt_regs *regs)
{
struct pt_regs *old_regs = set_irq_regs(regs);
unsigned long saved_tpr;
#if IRQ_DEBUG
{
unsigned long bsp, sp;
/*
* Note: if the interrupt happened while executing in
* the context switch routine (ia64_switch_to), we may
* get a spurious stack overflow here. This is
* because the register and the memory stack are not
* switched atomically.
*/
bsp = ia64_getreg(_IA64_REG_AR_BSP);
sp = ia64_getreg(_IA64_REG_SP);
if ((sp - bsp) < 1024) {
static DEFINE_RATELIMIT_STATE(ratelimit, 5 * HZ, 5);
if (__ratelimit(&ratelimit)) {
printk("ia64_handle_irq: DANGER: less than "
"1KB of free stack space!!\n"
"(bsp=0x%lx, sp=%lx)\n", bsp, sp);
}
}
}
#endif /* IRQ_DEBUG */
/*
* Always set TPR to limit maximum interrupt nesting depth to
* 16 (without this, it would be ~240, which could easily lead
* to kernel stack overflows).
*/
irq_enter();
saved_tpr = ia64_getreg(_IA64_REG_CR_TPR);
ia64_srlz_d();
while (vector != IA64_SPURIOUS_INT_VECTOR) {
int irq = local_vector_to_irq(vector);
if (unlikely(IS_LOCAL_TLB_FLUSH(vector))) {
smp_local_flush_tlb();
kstat_incr_irq_this_cpu(irq);
} else if (unlikely(IS_RESCHEDULE(vector))) {
scheduler_ipi();
kstat_incr_irq_this_cpu(irq);
} else {
ia64_setreg(_IA64_REG_CR_TPR, vector);
ia64_srlz_d();
if (unlikely(irq < 0)) {
printk(KERN_ERR "%s: Unexpected interrupt "
"vector %d on CPU %d is not mapped "
"to any IRQ!\n", __func__, vector,
smp_processor_id());
} else
generic_handle_irq(irq);
/*
* Disable interrupts and send EOI:
*/
local_irq_disable();
ia64_setreg(_IA64_REG_CR_TPR, saved_tpr);
}
ia64_eoi();
vector = ia64_get_ivr();
}
/*
* This must be done *after* the ia64_eoi(). For example, the keyboard softirq
* handler needs to be able to wait for further keyboard interrupts, which can't
* come through until ia64_eoi() has been done.
*/
irq_exit();
set_irq_regs(old_regs);
}
