xref: /openbmc/linux/arch/x86/kvm/irq.c (revision 4bacd796)
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 affilates.
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  */
34 int kvm_cpu_has_pending_timer(struct kvm_vcpu *vcpu)
35 {
36 	int ret;
37 
38 	ret = pit_has_pending_timer(vcpu);
39 	ret |= apic_has_pending_timer(vcpu);
40 
41 	return ret;
42 }
43 EXPORT_SYMBOL(kvm_cpu_has_pending_timer);
44 
45 /*
46  * check if there is pending interrupt without
47  * intack.
48  */
49 int kvm_cpu_has_interrupt(struct kvm_vcpu *v)
50 {
51 	struct kvm_pic *s;
52 
53 	if (!irqchip_in_kernel(v->kvm))
54 		return v->arch.interrupt.pending;
55 
56 	if (kvm_apic_has_interrupt(v) == -1) {	/* LAPIC */
57 		if (kvm_apic_accept_pic_intr(v)) {
58 			s = pic_irqchip(v->kvm);	/* PIC */
59 			return s->output;
60 		} else
61 			return 0;
62 	}
63 	return 1;
64 }
65 EXPORT_SYMBOL_GPL(kvm_cpu_has_interrupt);
66 
67 /*
68  * Read pending interrupt vector and intack.
69  */
70 int kvm_cpu_get_interrupt(struct kvm_vcpu *v)
71 {
72 	struct kvm_pic *s;
73 	int vector;
74 
75 	if (!irqchip_in_kernel(v->kvm))
76 		return v->arch.interrupt.nr;
77 
78 	vector = kvm_get_apic_interrupt(v);	/* APIC */
79 	if (vector == -1) {
80 		if (kvm_apic_accept_pic_intr(v)) {
81 			s = pic_irqchip(v->kvm);
82 			s->output = 0;		/* PIC */
83 			vector = kvm_pic_read_irq(v->kvm);
84 		}
85 	}
86 	return vector;
87 }
88 EXPORT_SYMBOL_GPL(kvm_cpu_get_interrupt);
89 
90 void kvm_inject_pending_timer_irqs(struct kvm_vcpu *vcpu)
91 {
92 	kvm_inject_apic_timer_irqs(vcpu);
93 	/* TODO: PIT, RTC etc. */
94 }
95 EXPORT_SYMBOL_GPL(kvm_inject_pending_timer_irqs);
96 
97 void __kvm_migrate_timers(struct kvm_vcpu *vcpu)
98 {
99 	__kvm_migrate_apic_timer(vcpu);
100 	__kvm_migrate_pit_timer(vcpu);
101 }
102