linux-sg2042/arch/ia64/kernel/irq.c

195 lines
4.6 KiB
C

/*
* 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 IRQs 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 losing 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
ia64_vector __ia64_irq_to_vector(int irq)
{
return irq_cfg[irq].vector;
}
unsigned int __ia64_local_vector_to_irq (ia64_vector vec)
{
return __get_cpu_var(vector_irq)[vec];
}
#endif
/*
* Interrupt statistics:
*/
atomic_t irq_err_count;
/*
* /proc/interrupts printing:
*/
int arch_show_interrupts(struct seq_file *p, int prec)
{
seq_printf(p, "ERR: %10u\n", atomic_read(&irq_err_count));
return 0;
}
#ifdef CONFIG_SMP
static char irq_redir [NR_IRQS]; // = { [0 ... NR_IRQS-1] = 1 };
void set_irq_affinity_info (unsigned int irq, int hwid, int redir)
{
if (irq < NR_IRQS) {
cpumask_copy(irq_get_irq_data(irq)->affinity,
cpumask_of(cpu_logical_id(hwid)));
irq_redir[irq] = (char) (redir & 0xff);
}
}
bool is_affinity_mask_valid(const struct cpumask *cpumask)
{
if (ia64_platform_is("sn2")) {
/* Only allow one CPU to be specified in the smp_affinity mask */
if (cpumask_weight(cpumask) != 1)
return false;
}
return true;
}
#endif /* CONFIG_SMP */
#ifdef CONFIG_HOTPLUG_CPU
unsigned int vectors_in_migration[NR_IRQS];
/*
* Since cpu_online_mask is already updated, we just need to check for
* affinity that has zeros
*/
static void migrate_irqs(void)
{
int irq, new_cpu;
for (irq=0; irq < NR_IRQS; irq++) {
struct irq_desc *desc = irq_to_desc(irq);
struct irq_data *data = irq_desc_get_irq_data(desc);
struct irq_chip *chip = irq_data_get_irq_chip(data);
if (irqd_irq_disabled(data))
continue;
/*
* 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 (irqd_is_per_cpu(data))
continue;
if (cpumask_any_and(data->affinity, cpu_online_mask)
>= nr_cpu_ids) {
/*
* Save it for phase 2 processing
*/
vectors_in_migration[irq] = irq;
new_cpu = cpumask_any(cpu_online_mask);
/*
* Al three are essential, currently WARN_ON.. maybe panic?
*/
if (chip && chip->irq_disable &&
chip->irq_enable && chip->irq_set_affinity) {
chip->irq_disable(data);
chip->irq_set_affinity(data,
cpumask_of(new_cpu), false);
chip->irq_enable(data);
} else {
WARN_ON((!chip || !chip->irq_disable ||
!chip->irq_enable ||
!chip->irq_set_affinity));
}
}
}
}
void fixup_irqs(void)
{
unsigned int irq;
extern void ia64_process_pending_intr(void);
extern volatile int time_keeper_id;
/* Mask ITV to disable timer */
ia64_set_itv(1 << 16);
/*
* Find a new timesync master
*/
if (smp_processor_id() == time_keeper_id) {
time_keeper_id = cpumask_first(cpu_online_mask);
printk ("CPU %d is now promoted to time-keeper master\n", time_keeper_id);
}
/*
* Phase 1: Locate IRQs 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]) {
struct pt_regs *old_regs = set_irq_regs(NULL);
vectors_in_migration[irq]=0;
generic_handle_irq(irq);
set_irq_regs(old_regs);
}
}
/*
* 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