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/*
* linux/arch/ia64/kernel/irq.c
*
* Copyright (C) 1998-2001 Hewlett-Packard Co
* Stephane Eranian <eranian@hpl.hp.com>
* David Mosberger-Tang <davidm@hpl.hp.com>
*
* 6/10/99: Updated to bring in sync with x86 version to facilitate
* support for SMP and different interrupt controllers.
*
* 09/15/00 Goutham Rao <goutham.rao@intel.com> Implemented pci_irq_to_vector
* PCI to vector allocation routine.
*/
#include <linux/config.h>
#include <linux/sched.h>
#include <linux/errno.h>
#include <linux/init.h>
#include <linux/interrupt.h>
#include <linux/ioport.h>
#include <linux/kernel_stat.h>
#include <linux/slab.h>
#include <linux/ptrace.h>
#include <linux/random.h> /* for rand_initialize_irq() */
#include <linux/signal.h>
#include <linux/smp.h>
#include <linux/smp_lock.h>
#include <linux/threads.h>
#include <asm/bitops.h>
#include <asm/delay.h>
#include <asm/io.h>
#include <asm/hw_irq.h>
#include <asm/machvec.h>
#include <asm/pgtable.h>
#include <asm/system.h>
#define IRQ_DEBUG 0
/* default base addr of IPI table */
unsigned long ipi_base_addr = (__IA64_UNCACHED_OFFSET | IA64_IPI_DEFAULT_BASE_ADDR);
/*
* Legacy IRQ to IA-64 vector translation table.
*/
__u8 isa_irq_to_vector_map[16] = {
/* 8259 IRQ translation, first 16 entries */
0x2f, 0x20, 0x2e, 0x2d, 0x2c, 0x2b, 0x2a, 0x29,
0x28, 0x27, 0x26, 0x25, 0x24, 0x23, 0x22, 0x21
};
int
ia64_alloc_irq (void)
{
static int next_irq = IA64_FIRST_DEVICE_VECTOR;
if (next_irq > IA64_LAST_DEVICE_VECTOR)
/* XXX could look for sharable vectors instead of panic'ing... */
panic("ia64_alloc_irq: out of interrupt vectors!");
return next_irq++;
}
extern unsigned int do_IRQ(unsigned long irq, struct pt_regs *regs);
/*
* 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)
{
unsigned long saved_tpr;
#ifdef CONFIG_SMP
# define IS_RESCHEDULE(vec) (vec == IA64_IPI_RESCHEDULE)
#else
# define IS_RESCHEDULE(vec) (0)
#endif
#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.
*/
asm ("mov %0=ar.bsp" : "=r"(bsp));
asm ("mov %0=sp" : "=r"(sp));
if ((sp - bsp) < 1024) {
static unsigned char count;
static long last_time;
if (jiffies - last_time > 5*HZ)
count = 0;
if (++count < 5) {
last_time = jiffies;
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).
*/
saved_tpr = ia64_get_tpr();
ia64_srlz_d();
while (vector != IA64_SPURIOUS_INT_VECTOR) {
if (!IS_RESCHEDULE(vector)) {
ia64_set_tpr(vector);
ia64_srlz_d();
do_IRQ(local_vector_to_irq(vector), regs);
/*
* Disable interrupts and send EOI:
*/
local_irq_disable();
ia64_set_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.
*/
if (local_softirq_pending())
do_softirq();
}
#ifdef CONFIG_SMP
extern void handle_IPI (int irq, void *dev_id, struct pt_regs *regs);
static struct irqaction ipi_irqaction = {
handler: handle_IPI,
flags: SA_INTERRUPT,
name: "IPI"
};
#endif
void
register_percpu_irq (ia64_vector vec, struct irqaction *action)
{
irq_desc_t *desc;
unsigned int irq;
for (irq = 0; irq < NR_IRQS; ++irq)
if (irq_to_vector(irq) == vec) {
desc = irq_desc(irq);
desc->status |= IRQ_PER_CPU;
desc->handler = &irq_type_ia64_lsapic;
if (action)
setup_irq(irq, action);
}
}
void __init
init_IRQ (void)
{
register_percpu_irq(IA64_SPURIOUS_INT_VECTOR, NULL);
#ifdef CONFIG_SMP
register_percpu_irq(IA64_IPI_VECTOR, &ipi_irqaction);
#endif
platform_irq_init();
}
void
ia64_send_ipi (int cpu, int vector, int delivery_mode, int redirect)
{
unsigned long ipi_addr;
unsigned long ipi_data;
unsigned long phys_cpu_id;
#ifdef CONFIG_SMP
phys_cpu_id = cpu_physical_id(cpu);
#else
phys_cpu_id = (ia64_get_lid() >> 16) & 0xffff;
#endif
/*
* cpu number is in 8bit ID and 8bit EID
*/
ipi_data = (delivery_mode << 8) | (vector & 0xff);
ipi_addr = ipi_base_addr | (phys_cpu_id << 4) | ((redirect & 1) << 3);
writeq(ipi_data, ipi_addr);
}
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