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 51 /* 52 * Vectors 0x30-0x3f are used for ISA interrupts. 53 * round up to the next 16-vector boundary 54 */ 55 #define ISA_IRQ_VECTOR(irq) (((FIRST_EXTERNAL_VECTOR + 16) & ~15) + irq) 56 57 /* 58 * Special IRQ vectors used by the SMP architecture, 0xf0-0xff 59 * 60 * some of the following vectors are 'rare', they are merged 61 * into a single vector (CALL_FUNCTION_VECTOR) to save vector space. 62 * TLB, reschedule and local APIC vectors are performance-critical. 63 */ 64 65 #define SPURIOUS_APIC_VECTOR 0xff 66 /* 67 * Sanity check 68 */ 69 #if ((SPURIOUS_APIC_VECTOR & 0x0F) != 0x0F) 70 # error SPURIOUS_APIC_VECTOR definition error 71 #endif 72 73 #define ERROR_APIC_VECTOR 0xfe 74 #define RESCHEDULE_VECTOR 0xfd 75 #define CALL_FUNCTION_VECTOR 0xfc 76 #define CALL_FUNCTION_SINGLE_VECTOR 0xfb 77 #define THERMAL_APIC_VECTOR 0xfa 78 #define THRESHOLD_APIC_VECTOR 0xf9 79 #define REBOOT_VECTOR 0xf8 80 81 /* 82 * Generic system vector for platform specific use 83 */ 84 #define X86_PLATFORM_IPI_VECTOR 0xf7 85 86 /* 87 * IRQ work vector: 88 */ 89 #define IRQ_WORK_VECTOR 0xf6 90 91 #define UV_BAU_MESSAGE 0xf5 92 #define DEFERRED_ERROR_VECTOR 0xf4 93 94 /* Vector on which hypervisor callbacks will be delivered */ 95 #define HYPERVISOR_CALLBACK_VECTOR 0xf3 96 97 /* Vector for KVM to deliver posted interrupt IPI */ 98 #ifdef CONFIG_HAVE_KVM 99 #define POSTED_INTR_VECTOR 0xf2 100 #define POSTED_INTR_WAKEUP_VECTOR 0xf1 101 #define POSTED_INTR_NESTED_VECTOR 0xf0 102 #endif 103 104 /* 105 * Local APIC timer IRQ vector is on a different priority level, 106 * to work around the 'lost local interrupt if more than 2 IRQ 107 * sources per level' errata. 108 */ 109 #define LOCAL_TIMER_VECTOR 0xef 110 111 #define NR_VECTORS 256 112 113 #ifdef CONFIG_X86_LOCAL_APIC 114 #define FIRST_SYSTEM_VECTOR LOCAL_TIMER_VECTOR 115 #else 116 #define FIRST_SYSTEM_VECTOR NR_VECTORS 117 #endif 118 119 #define FPU_IRQ 13 120 121 /* 122 * Size the maximum number of interrupts. 123 * 124 * If the irq_desc[] array has a sparse layout, we can size things 125 * generously - it scales up linearly with the maximum number of CPUs, 126 * and the maximum number of IO-APICs, whichever is higher. 127 * 128 * In other cases we size more conservatively, to not create too large 129 * static arrays. 130 */ 131 132 #define NR_IRQS_LEGACY 16 133 134 #define CPU_VECTOR_LIMIT (64 * NR_CPUS) 135 #define IO_APIC_VECTOR_LIMIT (32 * MAX_IO_APICS) 136 137 #if defined(CONFIG_X86_IO_APIC) && defined(CONFIG_PCI_MSI) 138 #define NR_IRQS \ 139 (CPU_VECTOR_LIMIT > IO_APIC_VECTOR_LIMIT ? \ 140 (NR_VECTORS + CPU_VECTOR_LIMIT) : \ 141 (NR_VECTORS + IO_APIC_VECTOR_LIMIT)) 142 #elif defined(CONFIG_X86_IO_APIC) 143 #define NR_IRQS (NR_VECTORS + IO_APIC_VECTOR_LIMIT) 144 #elif defined(CONFIG_PCI_MSI) 145 #define NR_IRQS (NR_VECTORS + CPU_VECTOR_LIMIT) 146 #else 147 #define NR_IRQS NR_IRQS_LEGACY 148 #endif 149 150 #endif /* _ASM_X86_IRQ_VECTORS_H */ 151