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#include <linux/errno.h>
#include <linux/signal.h>
#include <linux/sched.h>
#include <linux/ioport.h>
#include <linux/interrupt.h>
#include <linux/slab.h>
#include <linux/random.h>
#include <linux/init.h>
#include <linux/kernel_stat.h>
#include <linux/sysdev.h>
#include <linux/bitops.h>
#include <asm/atomic.h>
#include <asm/system.h>
#include <asm/io.h>
#include <asm/timer.h>
#include <asm/pgtable.h>
#include <asm/delay.h>
#include <asm/desc.h>
#include <asm/apic.h>
#include <asm/arch_hooks.h>
#include <asm/i8259.h>
/*
* Note that on a 486, we don't want to do a SIGFPE on an irq13
* as the irq is unreliable, and exception 16 works correctly
* (ie as explained in the intel literature). On a 386, you
* can't use exception 16 due to bad IBM design, so we have to
* rely on the less exact irq13.
*
* Careful.. Not only is IRQ13 unreliable, but it is also
* leads to races. IBM designers who came up with it should
* be shot.
*/
static irqreturn_t math_error_irq(int cpl, void *dev_id)
{
extern void math_error(void __user *);
outb(0,0xF0);
if (ignore_fpu_irq || !boot_cpu_data.hard_math)
return IRQ_NONE;
math_error((void __user *)get_irq_regs()->ip);
return IRQ_HANDLED;
}
/*
* New motherboards sometimes make IRQ 13 be a PCI interrupt,
* so allow interrupt sharing.
*/
static struct irqaction fpu_irq = {
.handler = math_error_irq,
.mask = CPU_MASK_NONE,
.name = "fpu",
};
void __init init_ISA_irqs (void)
{
int i;
#ifdef CONFIG_X86_LOCAL_APIC
init_bsp_APIC();
#endif
init_8259A(0);
/*
* 16 old-style INTA-cycle interrupts:
*/
for (i = 0; i < 16; i++) {
set_irq_chip_and_handler_name(i, &i8259A_chip,
handle_level_irq, "XT");
}
}
/* Overridden in paravirt.c */
void init_IRQ(void) __attribute__((weak, alias("native_init_IRQ")));
void __init native_init_IRQ(void)
{
int i;
/* all the set up before the call gates are initialised */
pre_intr_init_hook();
/*
* Cover the whole vector space, no vector can escape
* us. (some of these will be overridden and become
* 'special' SMP interrupts)
*/
for (i = 0; i < (NR_VECTORS - FIRST_EXTERNAL_VECTOR); i++) {
int vector = FIRST_EXTERNAL_VECTOR + i;
if (i >= NR_IRQS)
break;
/* SYSCALL_VECTOR was reserved in trap_init. */
if (!test_bit(vector, used_vectors))
set_intr_gate(vector, interrupt[i]);
}
/* setup after call gates are initialised (usually add in
* the architecture specific gates)
*/
intr_init_hook();
/*
* External FPU? Set up irq13 if so, for
* original braindamaged IBM FERR coupling.
*/
if (boot_cpu_data.hard_math && !cpu_has_fpu)
setup_irq(FPU_IRQ, &fpu_irq);
irq_ctx_init(smp_processor_id());
}
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