1 #ifndef _ASM_X86_IRQ_VECTORS_H
2 #define _ASM_X86_IRQ_VECTORS_H
3
4 #include <linux/threads.h>
5 /*
6 * Linux IRQ vector layout.
7 *
8 * There are 256 IDT entries (per CPU - each entry is 8 bytes) which can
9 * be defined by Linux. They are used as a jump table by the CPU when a
10 * given vector is triggered - by a CPU-external, CPU-internal or
11 * software-triggered event.
12 *
13 * Linux sets the kernel code address each entry jumps to early during
14 * bootup, and never changes them. This is the general layout of the
15 * IDT entries:
16 *
17 * Vectors 0 ... 31 : system traps and exceptions - hardcoded events
18 * Vectors 32 ... 127 : device interrupts
19 * Vector 128 : legacy int80 syscall interface
20 * Vectors 129 ... INVALIDATE_TLB_VECTOR_START-1 except 204 : device interrupts
21 * Vectors INVALIDATE_TLB_VECTOR_START ... 255 : special interrupts
22 *
23 * 64-bit x86 has per CPU IDT tables, 32-bit has one shared IDT table.
24 *
25 * This file enumerates the exact layout of them:
26 */
27
28 #define NMI_VECTOR 0x02
29 #define MCE_VECTOR 0x12
30
31 /*
32 * IDT vectors usable for external interrupt sources start at 0x20.
33 * (0x80 is the syscall vector, 0x30-0x3f are for ISA)
34 */
35 #define FIRST_EXTERNAL_VECTOR 0x20
36 /*
37 * We start allocating at 0x21 to spread out vectors evenly between
38 * priority levels. (0x80 is the syscall vector)
39 */
40 #define VECTOR_OFFSET_START 1
41
42 /*
43 * Reserve the lowest usable vector (and hence lowest priority) 0x20 for
44 * triggering cleanup after irq migration. 0x21-0x2f will still be used
45 * for device interrupts.
46 */
47 #define IRQ_MOVE_CLEANUP_VECTOR FIRST_EXTERNAL_VECTOR
48
49 #define IA32_SYSCALL_VECTOR 0x80
50 #ifdef CONFIG_X86_32
51 # define SYSCALL_VECTOR 0x80
52 #endif
53
54 /*
55 * Vectors 0x30-0x3f are used for ISA interrupts.
56 * round up to the next 16-vector boundary
57 */
58 #define IRQ0_VECTOR ((FIRST_EXTERNAL_VECTOR + 16) & ~15)
59
60 #define IRQ1_VECTOR (IRQ0_VECTOR + 1)
61 #define IRQ2_VECTOR (IRQ0_VECTOR + 2)
62 #define IRQ3_VECTOR (IRQ0_VECTOR + 3)
63 #define IRQ4_VECTOR (IRQ0_VECTOR + 4)
64 #define IRQ5_VECTOR (IRQ0_VECTOR + 5)
65 #define IRQ6_VECTOR (IRQ0_VECTOR + 6)
66 #define IRQ7_VECTOR (IRQ0_VECTOR + 7)
67 #define IRQ8_VECTOR (IRQ0_VECTOR + 8)
68 #define IRQ9_VECTOR (IRQ0_VECTOR + 9)
69 #define IRQ10_VECTOR (IRQ0_VECTOR + 10)
70 #define IRQ11_VECTOR (IRQ0_VECTOR + 11)
71 #define IRQ12_VECTOR (IRQ0_VECTOR + 12)
72 #define IRQ13_VECTOR (IRQ0_VECTOR + 13)
73 #define IRQ14_VECTOR (IRQ0_VECTOR + 14)
74 #define IRQ15_VECTOR (IRQ0_VECTOR + 15)
75
76 /*
77 * Special IRQ vectors used by the SMP architecture, 0xf0-0xff
78 *
79 * some of the following vectors are 'rare', they are merged
80 * into a single vector (CALL_FUNCTION_VECTOR) to save vector space.
81 * TLB, reschedule and local APIC vectors are performance-critical.
82 */
83
84 #define SPURIOUS_APIC_VECTOR 0xff
85 /*
86 * Sanity check
87 */
88 #if ((SPURIOUS_APIC_VECTOR & 0x0F) != 0x0F)
89 # error SPURIOUS_APIC_VECTOR definition error
90 #endif
91
92 #define ERROR_APIC_VECTOR 0xfe
93 #define RESCHEDULE_VECTOR 0xfd
94 #define CALL_FUNCTION_VECTOR 0xfc
95 #define CALL_FUNCTION_SINGLE_VECTOR 0xfb
96 #define THERMAL_APIC_VECTOR 0xfa
97 #define THRESHOLD_APIC_VECTOR 0xf9
98 #define REBOOT_VECTOR 0xf8
99
100 /*
101 * Generic system vector for platform specific use
102 */
103 #define X86_PLATFORM_IPI_VECTOR 0xf7
104
105 /*
106 * IRQ work vector:
107 */
108 #define IRQ_WORK_VECTOR 0xf6
109
110 #define UV_BAU_MESSAGE 0xf5
111
112 /* Xen vector callback to receive events in a HVM domain */
113 #define XEN_HVM_EVTCHN_CALLBACK 0xf3
114
115 /*
116 * Local APIC timer IRQ vector is on a different priority level,
117 * to work around the 'lost local interrupt if more than 2 IRQ
118 * sources per level' errata.
119 */
120 #define LOCAL_TIMER_VECTOR 0xef
121
122 /* up to 32 vectors used for spreading out TLB flushes: */
123 #if NR_CPUS <= 32
124 # define NUM_INVALIDATE_TLB_VECTORS (NR_CPUS)
125 #else
126 # define NUM_INVALIDATE_TLB_VECTORS (32)
127 #endif
128
129 #define INVALIDATE_TLB_VECTOR_END (0xee)
130 #define INVALIDATE_TLB_VECTOR_START \
131 (INVALIDATE_TLB_VECTOR_END-NUM_INVALIDATE_TLB_VECTORS+1)
132
133 #define NR_VECTORS 256
134
135 #define FPU_IRQ 13
136
137 #define FIRST_VM86_IRQ 3
138 #define LAST_VM86_IRQ 15
139
140 #ifndef __ASSEMBLY__
invalid_vm86_irq(int irq)141 static inline int invalid_vm86_irq(int irq)
142 {
143 return irq < FIRST_VM86_IRQ || irq > LAST_VM86_IRQ;
144 }
145 #endif
146
147 /*
148 * Size the maximum number of interrupts.
149 *
150 * If the irq_desc[] array has a sparse layout, we can size things
151 * generously - it scales up linearly with the maximum number of CPUs,
152 * and the maximum number of IO-APICs, whichever is higher.
153 *
154 * In other cases we size more conservatively, to not create too large
155 * static arrays.
156 */
157
158 #define NR_IRQS_LEGACY 16
159
160 #define IO_APIC_VECTOR_LIMIT ( 32 * MAX_IO_APICS )
161
162 #ifdef CONFIG_X86_IO_APIC
163 # define CPU_VECTOR_LIMIT (64 * NR_CPUS)
164 # define NR_IRQS \
165 (CPU_VECTOR_LIMIT > IO_APIC_VECTOR_LIMIT ? \
166 (NR_VECTORS + CPU_VECTOR_LIMIT) : \
167 (NR_VECTORS + IO_APIC_VECTOR_LIMIT))
168 #else /* !CONFIG_X86_IO_APIC: */
169 # define NR_IRQS NR_IRQS_LEGACY
170 #endif
171
172 #endif /* _ASM_X86_IRQ_VECTORS_H */
173