xref: /openbmc/linux/arch/x86/include/asm/irq_vectors.h (revision 4f3db074)
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 /* Vector for KVM to deliver posted interrupt IPI */
106 #ifdef CONFIG_HAVE_KVM
107 #define POSTED_INTR_VECTOR		0xf2
108 #endif
109 
110 /*
111  * IRQ work vector:
112  */
113 #define IRQ_WORK_VECTOR			0xf6
114 
115 #define UV_BAU_MESSAGE			0xf5
116 
117 /* Vector on which hypervisor callbacks will be delivered */
118 #define HYPERVISOR_CALLBACK_VECTOR	0xf3
119 
120 /*
121  * Local APIC timer IRQ vector is on a different priority level,
122  * to work around the 'lost local interrupt if more than 2 IRQ
123  * sources per level' errata.
124  */
125 #define LOCAL_TIMER_VECTOR		0xef
126 
127 #define NR_VECTORS			 256
128 
129 #ifdef CONFIG_X86_LOCAL_APIC
130 #define FIRST_SYSTEM_VECTOR		LOCAL_TIMER_VECTOR
131 #else
132 #define FIRST_SYSTEM_VECTOR		NR_VECTORS
133 #endif
134 
135 #define FPU_IRQ				  13
136 
137 #define	FIRST_VM86_IRQ			   3
138 #define LAST_VM86_IRQ			  15
139 
140 #ifndef __ASSEMBLY__
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