linux/arch/x86/kernel/irqinit.c
Kees Cook c94082656d x86: Use enum instead of literals for trap values
The traps are referred to by their numbers and it can be difficult to
understand them while reading the code without context. This patch adds
enumeration of the trap numbers and replaces the numbers with the correct
enum for x86.

Signed-off-by: Kees Cook <keescook@chromium.org>
Link: http://lkml.kernel.org/r/20120310000710.GA32667@www.outflux.net
Signed-off-by: H. Peter Anvin <hpa@zytor.com>
2012-03-09 16:47:54 -08:00

329 lines
7.7 KiB
C

#include <linux/linkage.h>
#include <linux/errno.h>
#include <linux/signal.h>
#include <linux/sched.h>
#include <linux/ioport.h>
#include <linux/interrupt.h>
#include <linux/timex.h>
#include <linux/random.h>
#include <linux/kprobes.h>
#include <linux/init.h>
#include <linux/kernel_stat.h>
#include <linux/device.h>
#include <linux/bitops.h>
#include <linux/acpi.h>
#include <linux/io.h>
#include <linux/delay.h>
#include <linux/atomic.h>
#include <asm/system.h>
#include <asm/timer.h>
#include <asm/hw_irq.h>
#include <asm/pgtable.h>
#include <asm/desc.h>
#include <asm/apic.h>
#include <asm/setup.h>
#include <asm/i8259.h>
#include <asm/traps.h>
#include <asm/prom.h>
/*
* ISA PIC or low IO-APIC triggered (INTA-cycle or APIC) interrupts:
* (these are usually mapped to vectors 0x30-0x3f)
*/
/*
* The IO-APIC gives us many more interrupt sources. Most of these
* are unused but an SMP system is supposed to have enough memory ...
* sometimes (mostly wrt. hw bugs) we get corrupted vectors all
* across the spectrum, so we really want to be prepared to get all
* of these. Plus, more powerful systems might have more than 64
* IO-APIC registers.
*
* (these are usually mapped into the 0x30-0xff vector range)
*/
#ifdef CONFIG_X86_32
/*
* 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)
{
outb(0, 0xF0);
if (ignore_fpu_irq || !boot_cpu_data.hard_math)
return IRQ_NONE;
math_error(get_irq_regs(), 0, X86_TRAP_MF);
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,
.name = "fpu",
.flags = IRQF_NO_THREAD,
};
#endif
/*
* IRQ2 is cascade interrupt to second interrupt controller
*/
static struct irqaction irq2 = {
.handler = no_action,
.name = "cascade",
.flags = IRQF_NO_THREAD,
};
DEFINE_PER_CPU(vector_irq_t, vector_irq) = {
[0 ... NR_VECTORS - 1] = -1,
};
int vector_used_by_percpu_irq(unsigned int vector)
{
int cpu;
for_each_online_cpu(cpu) {
if (per_cpu(vector_irq, cpu)[vector] != -1)
return 1;
}
return 0;
}
void __init init_ISA_irqs(void)
{
struct irq_chip *chip = legacy_pic->chip;
const char *name = chip->name;
int i;
#if defined(CONFIG_X86_64) || defined(CONFIG_X86_LOCAL_APIC)
init_bsp_APIC();
#endif
legacy_pic->init(0);
for (i = 0; i < legacy_pic->nr_legacy_irqs; i++)
irq_set_chip_and_handler_name(i, chip, handle_level_irq, name);
}
void __init init_IRQ(void)
{
int i;
/*
* We probably need a better place for this, but it works for
* now ...
*/
x86_add_irq_domains();
/*
* On cpu 0, Assign IRQ0_VECTOR..IRQ15_VECTOR's to IRQ 0..15.
* If these IRQ's are handled by legacy interrupt-controllers like PIC,
* then this configuration will likely be static after the boot. If
* these IRQ's are handled by more mordern controllers like IO-APIC,
* then this vector space can be freed and re-used dynamically as the
* irq's migrate etc.
*/
for (i = 0; i < legacy_pic->nr_legacy_irqs; i++)
per_cpu(vector_irq, 0)[IRQ0_VECTOR + i] = i;
x86_init.irqs.intr_init();
}
/*
* Setup the vector to irq mappings.
*/
void setup_vector_irq(int cpu)
{
#ifndef CONFIG_X86_IO_APIC
int irq;
/*
* On most of the platforms, legacy PIC delivers the interrupts on the
* boot cpu. But there are certain platforms where PIC interrupts are
* delivered to multiple cpu's. If the legacy IRQ is handled by the
* legacy PIC, for the new cpu that is coming online, setup the static
* legacy vector to irq mapping:
*/
for (irq = 0; irq < legacy_pic->nr_legacy_irqs; irq++)
per_cpu(vector_irq, cpu)[IRQ0_VECTOR + irq] = irq;
#endif
__setup_vector_irq(cpu);
}
static void __init smp_intr_init(void)
{
#ifdef CONFIG_SMP
#if defined(CONFIG_X86_64) || defined(CONFIG_X86_LOCAL_APIC)
/*
* The reschedule interrupt is a CPU-to-CPU reschedule-helper
* IPI, driven by wakeup.
*/
alloc_intr_gate(RESCHEDULE_VECTOR, reschedule_interrupt);
/* IPIs for invalidation */
#define ALLOC_INVTLB_VEC(NR) \
alloc_intr_gate(INVALIDATE_TLB_VECTOR_START+NR, \
invalidate_interrupt##NR)
switch (NUM_INVALIDATE_TLB_VECTORS) {
default:
ALLOC_INVTLB_VEC(31);
case 31:
ALLOC_INVTLB_VEC(30);
case 30:
ALLOC_INVTLB_VEC(29);
case 29:
ALLOC_INVTLB_VEC(28);
case 28:
ALLOC_INVTLB_VEC(27);
case 27:
ALLOC_INVTLB_VEC(26);
case 26:
ALLOC_INVTLB_VEC(25);
case 25:
ALLOC_INVTLB_VEC(24);
case 24:
ALLOC_INVTLB_VEC(23);
case 23:
ALLOC_INVTLB_VEC(22);
case 22:
ALLOC_INVTLB_VEC(21);
case 21:
ALLOC_INVTLB_VEC(20);
case 20:
ALLOC_INVTLB_VEC(19);
case 19:
ALLOC_INVTLB_VEC(18);
case 18:
ALLOC_INVTLB_VEC(17);
case 17:
ALLOC_INVTLB_VEC(16);
case 16:
ALLOC_INVTLB_VEC(15);
case 15:
ALLOC_INVTLB_VEC(14);
case 14:
ALLOC_INVTLB_VEC(13);
case 13:
ALLOC_INVTLB_VEC(12);
case 12:
ALLOC_INVTLB_VEC(11);
case 11:
ALLOC_INVTLB_VEC(10);
case 10:
ALLOC_INVTLB_VEC(9);
case 9:
ALLOC_INVTLB_VEC(8);
case 8:
ALLOC_INVTLB_VEC(7);
case 7:
ALLOC_INVTLB_VEC(6);
case 6:
ALLOC_INVTLB_VEC(5);
case 5:
ALLOC_INVTLB_VEC(4);
case 4:
ALLOC_INVTLB_VEC(3);
case 3:
ALLOC_INVTLB_VEC(2);
case 2:
ALLOC_INVTLB_VEC(1);
case 1:
ALLOC_INVTLB_VEC(0);
break;
}
/* IPI for generic function call */
alloc_intr_gate(CALL_FUNCTION_VECTOR, call_function_interrupt);
/* IPI for generic single function call */
alloc_intr_gate(CALL_FUNCTION_SINGLE_VECTOR,
call_function_single_interrupt);
/* Low priority IPI to cleanup after moving an irq */
set_intr_gate(IRQ_MOVE_CLEANUP_VECTOR, irq_move_cleanup_interrupt);
set_bit(IRQ_MOVE_CLEANUP_VECTOR, used_vectors);
/* IPI used for rebooting/stopping */
alloc_intr_gate(REBOOT_VECTOR, reboot_interrupt);
#endif
#endif /* CONFIG_SMP */
}
static void __init apic_intr_init(void)
{
smp_intr_init();
#ifdef CONFIG_X86_THERMAL_VECTOR
alloc_intr_gate(THERMAL_APIC_VECTOR, thermal_interrupt);
#endif
#ifdef CONFIG_X86_MCE_THRESHOLD
alloc_intr_gate(THRESHOLD_APIC_VECTOR, threshold_interrupt);
#endif
#if defined(CONFIG_X86_64) || defined(CONFIG_X86_LOCAL_APIC)
/* self generated IPI for local APIC timer */
alloc_intr_gate(LOCAL_TIMER_VECTOR, apic_timer_interrupt);
/* IPI for X86 platform specific use */
alloc_intr_gate(X86_PLATFORM_IPI_VECTOR, x86_platform_ipi);
/* IPI vectors for APIC spurious and error interrupts */
alloc_intr_gate(SPURIOUS_APIC_VECTOR, spurious_interrupt);
alloc_intr_gate(ERROR_APIC_VECTOR, error_interrupt);
/* IRQ work interrupts: */
# ifdef CONFIG_IRQ_WORK
alloc_intr_gate(IRQ_WORK_VECTOR, irq_work_interrupt);
# endif
#endif
}
void __init native_init_IRQ(void)
{
int i;
/* Execute any quirks before the call gates are initialised: */
x86_init.irqs.pre_vector_init();
apic_intr_init();
/*
* Cover the whole vector space, no vector can escape
* us. (some of these will be overridden and become
* 'special' SMP interrupts)
*/
for (i = FIRST_EXTERNAL_VECTOR; i < NR_VECTORS; i++) {
/* IA32_SYSCALL_VECTOR could be used in trap_init already. */
if (!test_bit(i, used_vectors))
set_intr_gate(i, interrupt[i-FIRST_EXTERNAL_VECTOR]);
}
if (!acpi_ioapic && !of_ioapic)
setup_irq(2, &irq2);
#ifdef CONFIG_X86_32
/*
* 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());
#endif
}