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/* SPDX-License-Identifier: GPL-2.0 */
#ifndef _ASM_X86_IRQ_VECTORS_H
#define _ASM_X86_IRQ_VECTORS_H
#include <linux/threads.h>
/*
* Linux IRQ vector layout.
*
* There are 256 IDT entries (per CPU - each entry is 8 bytes) which can
* be defined by Linux. They are used as a jump table by the CPU when a
* given vector is triggered - by a CPU-external, CPU-internal or
* software-triggered event.
*
* Linux sets the kernel code address each entry jumps to early during
* bootup, and never changes them. This is the general layout of the
* IDT entries:
*
* Vectors 0 ... 31 : system traps and exceptions - hardcoded events
* Vectors 32 ... 127 : device interrupts
* Vector 128 : legacy int80 syscall interface
* Vectors 129 ... LOCAL_TIMER_VECTOR-1
* Vectors LOCAL_TIMER_VECTOR ... 255 : special interrupts
*
* 64-bit x86 has per CPU IDT tables, 32-bit has one shared IDT table.
*
* This file enumerates the exact layout of them:
*/
/* This is used as an interrupt vector when programming the APIC. */
#define NMI_VECTOR 0x02
/*
* IDT vectors usable for external interrupt sources start at 0x20.
* (0x80 is the syscall vector, 0x30-0x3f are for ISA)
*/
#define FIRST_EXTERNAL_VECTOR 0x20
/*
* Reserve the lowest usable vector (and hence lowest priority) 0x20 for
* triggering cleanup after irq migration. 0x21-0x2f will still be used
* for device interrupts.
*/
#define IRQ_MOVE_CLEANUP_VECTOR FIRST_EXTERNAL_VECTOR
#define IA32_SYSCALL_VECTOR 0x80
/*
* Vectors 0x30-0x3f are used for ISA interrupts.
* round up to the next 16-vector boundary
*/
#define ISA_IRQ_VECTOR(irq) (((FIRST_EXTERNAL_VECTOR + 16) & ~15) + irq)
/*
* Special IRQ vectors used by the SMP architecture, 0xf0-0xff
*
* some of the following vectors are 'rare', they are merged
* into a single vector (CALL_FUNCTION_VECTOR) to save vector space.
* TLB, reschedule and local APIC vectors are performance-critical.
*/
#define SPURIOUS_APIC_VECTOR 0xff
/*
* Sanity check
*/
#if ((SPURIOUS_APIC_VECTOR & 0x0F) != 0x0F)
# error SPURIOUS_APIC_VECTOR definition error
#endif
#define ERROR_APIC_VECTOR 0xfe
#define RESCHEDULE_VECTOR 0xfd
#define CALL_FUNCTION_VECTOR 0xfc
#define CALL_FUNCTION_SINGLE_VECTOR 0xfb
#define THERMAL_APIC_VECTOR 0xfa
#define THRESHOLD_APIC_VECTOR 0xf9
#define REBOOT_VECTOR 0xf8
/*
* Generic system vector for platform specific use
*/
#define X86_PLATFORM_IPI_VECTOR 0xf7
/*
* IRQ work vector:
*/
#define IRQ_WORK_VECTOR 0xf6
/* 0xf5 - unused, was UV_BAU_MESSAGE */
#define DEFERRED_ERROR_VECTOR 0xf4
/* Vector on which hypervisor callbacks will be delivered */
#define HYPERVISOR_CALLBACK_VECTOR 0xf3
/* Vector for KVM to deliver posted interrupt IPI */
#ifdef CONFIG_HAVE_KVM
#define POSTED_INTR_VECTOR 0xf2
#define POSTED_INTR_WAKEUP_VECTOR 0xf1
#define POSTED_INTR_NESTED_VECTOR 0xf0
#endif
#define MANAGED_IRQ_SHUTDOWN_VECTOR 0xef
#if IS_ENABLED(CONFIG_HYPERV)
#define HYPERV_REENLIGHTENMENT_VECTOR 0xee
#define HYPERV_STIMER0_VECTOR 0xed
#endif
#define LOCAL_TIMER_VECTOR 0xec
#define NR_VECTORS 256
#ifdef CONFIG_X86_LOCAL_APIC
#define FIRST_SYSTEM_VECTOR LOCAL_TIMER_VECTOR
#else
#define FIRST_SYSTEM_VECTOR NR_VECTORS
#endif
#define NR_EXTERNAL_VECTORS (FIRST_SYSTEM_VECTOR - FIRST_EXTERNAL_VECTOR)
#define NR_SYSTEM_VECTORS (NR_VECTORS - FIRST_SYSTEM_VECTOR)
/*
* Size the maximum number of interrupts.
*
* If the irq_desc[] array has a sparse layout, we can size things
* generously - it scales up linearly with the maximum number of CPUs,
* and the maximum number of IO-APICs, whichever is higher.
*
* In other cases we size more conservatively, to not create too large
* static arrays.
*/
#define NR_IRQS_LEGACY 16
#define CPU_VECTOR_LIMIT (64 * NR_CPUS)
#define IO_APIC_VECTOR_LIMIT (32 * MAX_IO_APICS)
#if defined(CONFIG_X86_IO_APIC) && defined(CONFIG_PCI_MSI)
#define NR_IRQS \
(CPU_VECTOR_LIMIT > IO_APIC_VECTOR_LIMIT ? \
(NR_VECTORS + CPU_VECTOR_LIMIT) : \
(NR_VECTORS + IO_APIC_VECTOR_LIMIT))
#elif defined(CONFIG_X86_IO_APIC)
#define NR_IRQS (NR_VECTORS + IO_APIC_VECTOR_LIMIT)
#elif defined(CONFIG_PCI_MSI)
#define NR_IRQS (NR_VECTORS + CPU_VECTOR_LIMIT)
#else
#define NR_IRQS NR_IRQS_LEGACY
#endif
#endif /* _ASM_X86_IRQ_VECTORS_H */
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