/* SPDX-License-Identifier: GPL-2.0-only */
/*
 * irq.h: in kernel interrupt controller related definitions
 * Copyright (c) 2007, Intel Corporation.
 *
 * Authors:
 *   Yaozu (Eddie) Dong <Eddie.dong@intel.com>
 */

#ifndef __IRQ_H
#define __IRQ_H

#include <linux/mm_types.h>
#include <linux/hrtimer.h>
#include <linux/kvm_host.h>
#include <linux/spinlock.h>

#include <kvm/iodev.h>
#include "lapic.h"

#ifdef CONFIG_KVM_IOAPIC

#define PIC_NUM_PINS 16
#define SELECT_PIC(irq) \
	((irq) < 8 ? KVM_IRQCHIP_PIC_MASTER : KVM_IRQCHIP_PIC_SLAVE)

struct kvm;
struct kvm_vcpu;

struct kvm_kpic_state {
	u8 last_irr;	/* edge detection */
	u8 irr;		/* interrupt request register */
	u8 imr;		/* interrupt mask register */
	u8 isr;		/* interrupt service register */
	u8 priority_add;	/* highest irq priority */
	u8 irq_base;
	u8 read_reg_select;
	u8 poll;
	u8 special_mask;
	u8 init_state;
	u8 auto_eoi;
	u8 rotate_on_auto_eoi;
	u8 special_fully_nested_mode;
	u8 init4;		/* true if 4 byte init */
	u8 elcr;		/* PIIX edge/trigger selection */
	u8 elcr_mask;
	u8 isr_ack;	/* interrupt ack detection */
	struct kvm_pic *pics_state;
};

struct kvm_pic {
	spinlock_t lock;
	bool wakeup_needed;
	unsigned pending_acks;
	struct kvm *kvm;
	struct kvm_kpic_state pics[2]; /* 0 is master pic, 1 is slave pic */
	int output;		/* intr from master PIC */
	struct kvm_io_device dev_master;
	struct kvm_io_device dev_slave;
	struct kvm_io_device dev_elcr;
	unsigned long irq_states[PIC_NUM_PINS];
};

int kvm_pic_init(struct kvm *kvm);
void kvm_pic_destroy(struct kvm *kvm);
int kvm_pic_read_irq(struct kvm *kvm);
void kvm_pic_update_irq(struct kvm_pic *s);
int kvm_pic_set_irq(struct kvm_kernel_irq_routing_entry *e, struct kvm *kvm,
		    int irq_source_id, int level, bool line_status);

int kvm_setup_default_ioapic_and_pic_routing(struct kvm *kvm);

int kvm_vm_ioctl_get_irqchip(struct kvm *kvm, struct kvm_irqchip *chip);
int kvm_vm_ioctl_set_irqchip(struct kvm *kvm, struct kvm_irqchip *chip);

static inline int irqchip_full(struct kvm *kvm)
{
	int mode = kvm->arch.irqchip_mode;

	/* Matches smp_wmb() when setting irqchip_mode */
	smp_rmb();
	return mode == KVM_IRQCHIP_KERNEL;
}
#else /* CONFIG_KVM_IOAPIC */
static __always_inline int irqchip_full(struct kvm *kvm)
{
	return false;
}
#endif

static inline int pic_in_kernel(struct kvm *kvm)
{
	return irqchip_full(kvm);
}


static inline int irqchip_split(struct kvm *kvm)
{
	int mode = kvm->arch.irqchip_mode;

	/* Matches smp_wmb() when setting irqchip_mode */
	smp_rmb();
	return mode == KVM_IRQCHIP_SPLIT;
}

static inline int irqchip_in_kernel(struct kvm *kvm)
{
	int mode = kvm->arch.irqchip_mode;

	/* Matches smp_wmb() when setting irqchip_mode */
	smp_rmb();
	return mode != KVM_IRQCHIP_NONE;
}

int kvm_cpu_has_injectable_intr(struct kvm_vcpu *v);
int kvm_cpu_has_interrupt(struct kvm_vcpu *vcpu);
int kvm_cpu_has_extint(struct kvm_vcpu *v);
int kvm_cpu_get_extint(struct kvm_vcpu *v);
int kvm_cpu_get_interrupt(struct kvm_vcpu *v);

static inline void kvm_warn_on_lost_irq(struct kvm_vcpu *vcpu)
{
	/*
	 * WARN if an IRQ was lost between detecting the IRQ and grabbing the
	 * IRQ for injection, unless it's possible the lost IRQ was due to one
	 * of the exceptional cases below.
	 *
	 * If the VM has an in-kernel PIC, the ExtINT handling that's routed
	 * through KVM's virtual PIC is tracked per-VM, not per-vCPU.  If
	 * another vCPU grabs the IRQ, or deasserts the interrupt (which is
	 * level-triggered), then it's both expected and "fine" for an IRQ
	 * seemingly be "lost" from this vCPU's perspective.
	 *
	 * Similarly, Xen's event channel isn't entirely within KVM's control,
	 * e.g. Xen emulation can be disabled entirely per-VM, or the guest
	 * can desassert an IRQ by writing to shared memory.
	 */
	WARN_ON_ONCE(!pic_in_kernel(vcpu->kvm) && !IS_ENABLED(CONFIG_KVM_XEN));
}

void kvm_inject_pending_timer_irqs(struct kvm_vcpu *vcpu);
void kvm_inject_apic_timer_irqs(struct kvm_vcpu *vcpu);
void kvm_apic_nmi_wd_deliver(struct kvm_vcpu *vcpu);
void __kvm_migrate_apic_timer(struct kvm_vcpu *vcpu);
void __kvm_migrate_pit_timer(struct kvm_vcpu *vcpu);
void __kvm_migrate_timers(struct kvm_vcpu *vcpu);

int apic_has_pending_timer(struct kvm_vcpu *vcpu);

#endif