xref: /openbmc/qemu/hw/core/irq.c (revision d6032e06)
1 /*
2  * QEMU IRQ/GPIO common code.
3  *
4  * Copyright (c) 2007 CodeSourcery.
5  *
6  * Permission is hereby granted, free of charge, to any person obtaining a copy
7  * of this software and associated documentation files (the "Software"), to deal
8  * in the Software without restriction, including without limitation the rights
9  * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
10  * copies of the Software, and to permit persons to whom the Software is
11  * furnished to do so, subject to the following conditions:
12  *
13  * The above copyright notice and this permission notice shall be included in
14  * all copies or substantial portions of the Software.
15  *
16  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
17  * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
18  * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
19  * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
20  * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
21  * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
22  * THE SOFTWARE.
23  */
24 #include "qemu-common.h"
25 #include "hw/irq.h"
26 
27 struct IRQState {
28     qemu_irq_handler handler;
29     void *opaque;
30     int n;
31 };
32 
33 void qemu_set_irq(qemu_irq irq, int level)
34 {
35     if (!irq)
36         return;
37 
38     irq->handler(irq->opaque, irq->n, level);
39 }
40 
41 qemu_irq *qemu_extend_irqs(qemu_irq *old, int n_old, qemu_irq_handler handler,
42                            void *opaque, int n)
43 {
44     qemu_irq *s;
45     struct IRQState *p;
46     int i;
47 
48     if (!old) {
49         n_old = 0;
50     }
51     s = old ? g_renew(qemu_irq, old, n + n_old) : g_new(qemu_irq, n);
52     p = old ? g_renew(struct IRQState, s[0], n + n_old) :
53                 g_new(struct IRQState, n);
54     for (i = 0; i < n + n_old; i++) {
55         if (i >= n_old) {
56             p->handler = handler;
57             p->opaque = opaque;
58             p->n = i;
59         }
60         s[i] = p;
61         p++;
62     }
63     return s;
64 }
65 
66 qemu_irq *qemu_allocate_irqs(qemu_irq_handler handler, void *opaque, int n)
67 {
68     return qemu_extend_irqs(NULL, 0, handler, opaque, n);
69 }
70 
71 qemu_irq qemu_allocate_irq(qemu_irq_handler handler, void *opaque, int n)
72 {
73     struct IRQState *irq;
74 
75     irq = g_new(struct IRQState, 1);
76     irq->handler = handler;
77     irq->opaque = opaque;
78     irq->n = n;
79 
80     return irq;
81 }
82 
83 void qemu_free_irqs(qemu_irq *s)
84 {
85     g_free(s[0]);
86     g_free(s);
87 }
88 
89 void qemu_free_irq(qemu_irq irq)
90 {
91     g_free(irq);
92 }
93 
94 static void qemu_notirq(void *opaque, int line, int level)
95 {
96     struct IRQState *irq = opaque;
97 
98     irq->handler(irq->opaque, irq->n, !level);
99 }
100 
101 qemu_irq qemu_irq_invert(qemu_irq irq)
102 {
103     /* The default state for IRQs is low, so raise the output now.  */
104     qemu_irq_raise(irq);
105     return qemu_allocate_irqs(qemu_notirq, irq, 1)[0];
106 }
107 
108 static void qemu_splitirq(void *opaque, int line, int level)
109 {
110     struct IRQState **irq = opaque;
111     irq[0]->handler(irq[0]->opaque, irq[0]->n, level);
112     irq[1]->handler(irq[1]->opaque, irq[1]->n, level);
113 }
114 
115 qemu_irq qemu_irq_split(qemu_irq irq1, qemu_irq irq2)
116 {
117     qemu_irq *s = g_malloc0(2 * sizeof(qemu_irq));
118     s[0] = irq1;
119     s[1] = irq2;
120     return qemu_allocate_irqs(qemu_splitirq, s, 1)[0];
121 }
122 
123 static void proxy_irq_handler(void *opaque, int n, int level)
124 {
125     qemu_irq **target = opaque;
126 
127     if (*target) {
128         qemu_set_irq((*target)[n], level);
129     }
130 }
131 
132 qemu_irq *qemu_irq_proxy(qemu_irq **target, int n)
133 {
134     return qemu_allocate_irqs(proxy_irq_handler, target, n);
135 }
136 
137 void qemu_irq_intercept_in(qemu_irq *gpio_in, qemu_irq_handler handler, int n)
138 {
139     int i;
140     qemu_irq *old_irqs = qemu_allocate_irqs(NULL, NULL, n);
141     for (i = 0; i < n; i++) {
142         *old_irqs[i] = *gpio_in[i];
143         gpio_in[i]->handler = handler;
144         gpio_in[i]->opaque = old_irqs;
145     }
146 }
147 
148 void qemu_irq_intercept_out(qemu_irq **gpio_out, qemu_irq_handler handler, int n)
149 {
150     qemu_irq *old_irqs = *gpio_out;
151     *gpio_out = qemu_allocate_irqs(handler, old_irqs, n);
152 }
153