mirror_ubuntu-kernels/arch/x86/kernel/irqinit.c

108 lines
2.9 KiB
C

// SPDX-License-Identifier: GPL-2.0
#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/irq.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/pgtable.h>
#include <linux/atomic.h>
#include <asm/timer.h>
#include <asm/hw_irq.h>
#include <asm/desc.h>
#include <asm/io_apic.h>
#include <asm/acpi.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)
*/
DEFINE_PER_CPU(vector_irq_t, vector_irq) = {
[0 ... NR_VECTORS - 1] = VECTOR_UNUSED,
};
void __init init_ISA_irqs(void)
{
struct irq_chip *chip = legacy_pic->chip;
int i;
/*
* Try to set up the through-local-APIC virtual wire mode earlier.
*
* On some 32-bit UP machines, whose APIC has been disabled by BIOS
* and then got re-enabled by "lapic", it hangs at boot time without this.
*/
init_bsp_APIC();
legacy_pic->init(0);
for (i = 0; i < nr_legacy_irqs(); i++) {
irq_set_chip_and_handler(i, chip, handle_level_irq);
irq_set_status_flags(i, IRQ_LEVEL);
}
}
void __init init_IRQ(void)
{
int i;
/*
* On cpu 0, Assign ISA_IRQ_VECTOR(irq) 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 IRQs are handled by more modern 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 < nr_legacy_irqs(); i++)
per_cpu(vector_irq, 0)[ISA_IRQ_VECTOR(i)] = irq_to_desc(i);
BUG_ON(irq_init_percpu_irqstack(smp_processor_id()));
x86_init.irqs.intr_init();
}
void __init native_init_IRQ(void)
{
/* Execute any quirks before the call gates are initialised: */
x86_init.irqs.pre_vector_init();
idt_setup_apic_and_irq_gates();
lapic_assign_system_vectors();
if (!acpi_ioapic && !of_ioapic && nr_legacy_irqs()) {
/* IRQ2 is cascade interrupt to second interrupt controller */
if (request_irq(2, no_action, IRQF_NO_THREAD, "cascade", NULL))
pr_err("%s: request_irq() failed\n", "cascade");
}
}