/*
* linux/arch/ia64/kernel/irq.c
*
* Copyright (C) 1992, 1998 Linus Torvalds, Ingo Molnar
*
* This file contains the code used by various IRQ handling routines:
* asking for different IRQ's should be done through these routines
* instead of just grabbing them. Thus setups with different IRQ numbers
* shouldn't result in any weird surprises, and installing new handlers
* should be easier.
*
* Copyright (C) Ashok Raj<ashok.raj@intel.com>, Intel Corporation 2004
*
* 4/14/2004: Added code to handle cpu migration and do safe irq
* migration without lossing interrupts for iosapic
* architecture.
*/
#include <asm/delay.h>
#include <asm/uaccess.h>
#include <linux/module.h>
#include <linux/seq_file.h>
#include <linux/interrupt.h>
#include <linux/kernel_stat.h>
/*
* 'what should we do if we get a hw irq event on an illegal vector'.
* each architecture has to answer this themselves.
*/
void ack_bad_irq(unsigned int irq)
{
printk(KERN_ERR "Unexpected irq vector 0x%x on CPU %u!\n", irq, smp_processor_id());
}
#ifdef CONFIG_IA64_GENERIC
unsigned int __ia64_local_vector_to_irq (ia64_vector vec)
{
return (unsigned int) vec;
}
#endif
/*
* Interrupt statistics:
*/
atomic_t irq_err_count;
/*
* /proc/interrupts printing:
*/
int show_interrupts(struct seq_file *p, void *v)
{
int i = *(loff_t *) v, j;
struct irqaction * action;
unsigned long flags;
if (i == 0) {
seq_printf(p, " ");
for (j=0; j<NR_CPUS; j++)
if (cpu_online(j))
seq_printf(p, "CPU%d ",j);
seq_putc(p, '\n');
}
if (i < NR_IRQS) {
spin_lock_irqsave(&irq_desc[i].lock, flags);
action = irq_desc[i].action;
if (!action)
goto skip;
seq_printf(p, "%3d: ",i);
#ifndef CONFIG_SMP
seq_printf(p, "%10u ", kstat_irqs(i));
#else
for (j = 0; j < NR_CPUS; j++)
if (cpu_online(j))
seq_printf(p, "%10u ", kstat_cpu(j).irqs[i]);
#endif
seq_printf(p, " %14s", irq_desc[i].handler->typename);
seq_printf(p, " %s", action->name);
for (action=action->next; action; action = action->next)
seq_printf(p, ", %s", action->name);
seq_putc(p, '\n');
skip:
spin_unlock_irqrestore(&irq_desc[i].lock, flags);
} else if (i == NR_IRQS)
seq_printf(p, "ERR: %10u\n", atomic_read(&irq_err_count));
return 0;
}
#ifdef CONFIG_SMP
/*
* This is updated when the user sets irq affinity via /proc
*/
static cpumask_t __cacheline_aligned pending_irq_cpumask[NR_IRQS];
static unsigned long pending_irq_redir[BITS_TO_LONGS(NR_IRQS)];
static char irq_redir [NR_IRQS]; // = { [0 ... NR_IRQS-1] = 1 };
/*
* Arch specific routine for deferred write to iosapic rte to reprogram
* intr destination.
*/
void proc_set_irq_affinity(unsigned int irq, cpumask_t mask_val)
{
pending_irq_cpumask[irq] = mask_val;
}
void set_irq_affinity_info (unsigned int irq, int hwid, int redir)
{
cpumask_t mask = CPU_MASK_NONE;
cpu_set(cpu_logical_id(hwid), mask);
if (irq < NR_IRQS) {
irq_affinity[irq] = mask;
irq_redir[irq] = (char) (redir & 0xff);
}
}
void move_irq(int irq)
{
/* note - we hold desc->lock */
cpumask_t tmp;
irq_desc_t *desc = irq_descp(irq);
int redir = test_bit(irq, pending_irq_redir);
if (unlikely(!desc->handler->set_affinity))
return;
if (!cpus_empty(pending_irq_cpumask[irq])) {
cpus_and(tmp, pending_irq_cpumask[irq], cpu_online_map);
if (unlikely(!cpus_empty(tmp))) {
desc->handler->set_affinity(irq | (redir ? IA64_IRQ_REDIRECTED : 0),
pending_irq_cpumask[irq]);
}
cpus_clear(pending_irq_cpumask[irq]);
}
}
#endif /* CONFIG_SMP */
#ifdef CONFIG_HOTPLUG_CPU
unsigned int vectors_in_migration[NR_IRQS];
/*
* Since cpu_online_map is already updated, we just need to check for
* affinity that has zeros
*/
static void migrate_irqs(void)
{
cpumask_t mask;
irq_desc_t *desc;
int irq, new_cpu;
for (irq=0; irq < NR_IRQS; irq++) {
desc = irq_descp(irq);
/*
* No handling for now.
* TBD: Implement a disable function so we can now
* tell CPU not to respond to these local intr sources.
* such as ITV,CPEI,MCA etc.
*/
if (desc->status == IRQ_PER_CPU)
continue;
cpus_and(mask, irq_affinity[irq], cpu_online_map);
if (any_online_cpu(mask) == NR_CPUS) {
/*
* Save it for phase 2 processing
*/
vectors_in_migration[irq] = irq;
new_cpu = any_online_cpu(cpu_online_map);
mask = cpumask_of_cpu(new_cpu);
/*
* Al three are essential, currently WARN_ON.. maybe panic?
*/
if (desc->handler && desc->handler->disable &&
desc->handler->enable && desc->handler->set_affinity) {
desc->handler->disable(irq);
desc->handler->set_affinity(irq, mask);
desc->handler->enable(irq);
} else {
WARN_ON((!(desc->handler) || !(desc->handler->disable) ||
!(desc->handler->enable) ||
!(desc->handler->set_affinity)));
}
}
}
}
void fixup_irqs(void)
{
unsigned int irq;
extern void ia64_process_pending_intr(void);
ia64_set_itv(1<<16);
/*
* Phase 1: Locate irq's bound to this cpu and
* relocate them for cpu removal.
*/
migrate_irqs();
/*
* Phase 2: Perform interrupt processing for all entries reported in
* local APIC.
*/
ia64_process_pending_intr();
/*
* Phase 3: Now handle any interrupts not captured in local APIC.
* This is to account for cases that device interrupted during the time the
* rte was being disabled and re-programmed.
*/
for (irq=0; irq < NR_IRQS; irq++) {
if (vectors_in_migration[irq]) {
vectors_in_migration[irq]=0;
__do_IRQ(irq, NULL);
}
}
/*
* Now let processor die. We do irq disable and max_xtp() to
* ensure there is no more interrupts routed to this processor.
* But the local timer interrupt can have 1 pending which we
* take care in timer_interrupt().
*/
max_xtp();
local_irq_disable();
}
#endif
