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-rw-r--r--arch/x86/include/asm/irq_vectors.h149
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diff --git a/arch/x86/include/asm/irq_vectors.h b/arch/x86/include/asm/irq_vectors.h
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+++ b/arch/x86/include/asm/irq_vectors.h
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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 */