summaryrefslogtreecommitdiff
path: root/tools/arch/x86/include/asm/irq_vectors.h
blob: d18bfb238f660fcccdfdf444a60720f03163e4d5 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
/* 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

#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 */
#define POSTED_INTR_VECTOR		0xf2
#define POSTED_INTR_WAKEUP_VECTOR	0xf1
#define POSTED_INTR_NESTED_VECTOR	0xf0

#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 */