1/*
2 * irq.c: API for in kernel interrupt controller
3 * Copyright (c) 2007, Intel Corporation.
4 * Copyright 2009 Red Hat, Inc. and/or its affiliates.
5 *
6 * This program is free software; you can redistribute it and/or modify it
7 * under the terms and conditions of the GNU General Public License,
8 * version 2, as published by the Free Software Foundation.
9 *
10 * This program is distributed in the hope it will be useful, but WITHOUT
11 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
12 * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
13 * more details.
14 *
15 * You should have received a copy of the GNU General Public License along with
16 * this program; if not, write to the Free Software Foundation, Inc., 59 Temple
17 * Place - Suite 330, Boston, MA 02111-1307 USA.
18 * Authors:
19 *   Yaozu (Eddie) Dong <Eddie.dong@intel.com>
20 *
21 */
22
23#include <linux/module.h>
24#include <linux/kvm_host.h>
25
26#include "irq.h"
27#include "i8254.h"
28#include "x86.h"
29
30/*
31 * check if there are pending timer events
32 * to be processed.
33 */
34int kvm_cpu_has_pending_timer(struct kvm_vcpu *vcpu)
35{
36	return apic_has_pending_timer(vcpu);
37}
38EXPORT_SYMBOL(kvm_cpu_has_pending_timer);
39
40/*
41 * check if there is a pending userspace external interrupt
42 */
43static int pending_userspace_extint(struct kvm_vcpu *v)
44{
45	return v->arch.pending_external_vector != -1;
46}
47
48/*
49 * check if there is pending interrupt from
50 * non-APIC source without intack.
51 */
52static int kvm_cpu_has_extint(struct kvm_vcpu *v)
53{
54	u8 accept = kvm_apic_accept_pic_intr(v);
55
56	if (accept) {
57		if (irqchip_split(v->kvm))
58			return pending_userspace_extint(v);
59		else
60			return pic_irqchip(v->kvm)->output;
61	} else
62		return 0;
63}
64
65/*
66 * check if there is injectable interrupt:
67 * when virtual interrupt delivery enabled,
68 * interrupt from apic will handled by hardware,
69 * we don't need to check it here.
70 */
71int kvm_cpu_has_injectable_intr(struct kvm_vcpu *v)
72{
73	if (!lapic_in_kernel(v))
74		return v->arch.interrupt.pending;
75
76	if (kvm_cpu_has_extint(v))
77		return 1;
78
79	if (kvm_vcpu_apic_vid_enabled(v))
80		return 0;
81
82	return kvm_apic_has_interrupt(v) != -1; /* LAPIC */
83}
84
85/*
86 * check if there is pending interrupt without
87 * intack.
88 */
89int kvm_cpu_has_interrupt(struct kvm_vcpu *v)
90{
91	if (!lapic_in_kernel(v))
92		return v->arch.interrupt.pending;
93
94	if (kvm_cpu_has_extint(v))
95		return 1;
96
97	return kvm_apic_has_interrupt(v) != -1;	/* LAPIC */
98}
99EXPORT_SYMBOL_GPL(kvm_cpu_has_interrupt);
100
101/*
102 * Read pending interrupt(from non-APIC source)
103 * vector and intack.
104 */
105static int kvm_cpu_get_extint(struct kvm_vcpu *v)
106{
107	if (kvm_cpu_has_extint(v)) {
108		if (irqchip_split(v->kvm)) {
109			int vector = v->arch.pending_external_vector;
110
111			v->arch.pending_external_vector = -1;
112			return vector;
113		} else
114			return kvm_pic_read_irq(v->kvm); /* PIC */
115	} else
116		return -1;
117}
118
119/*
120 * Read pending interrupt vector and intack.
121 */
122int kvm_cpu_get_interrupt(struct kvm_vcpu *v)
123{
124	int vector;
125
126	if (!lapic_in_kernel(v))
127		return v->arch.interrupt.nr;
128
129	vector = kvm_cpu_get_extint(v);
130
131	if (vector != -1)
132		return vector;			/* PIC */
133
134	return kvm_get_apic_interrupt(v);	/* APIC */
135}
136EXPORT_SYMBOL_GPL(kvm_cpu_get_interrupt);
137
138void kvm_inject_pending_timer_irqs(struct kvm_vcpu *vcpu)
139{
140	kvm_inject_apic_timer_irqs(vcpu);
141	/* TODO: PIT, RTC etc. */
142}
143EXPORT_SYMBOL_GPL(kvm_inject_pending_timer_irqs);
144
145void __kvm_migrate_timers(struct kvm_vcpu *vcpu)
146{
147	__kvm_migrate_apic_timer(vcpu);
148	__kvm_migrate_pit_timer(vcpu);
149}
150