xref: /openbmc/qemu/hw/core/irq.c (revision 49ab747f)
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 
72 void qemu_free_irqs(qemu_irq *s)
73 {
74     g_free(s[0]);
75     g_free(s);
76 }
77 
78 static void qemu_notirq(void *opaque, int line, int level)
79 {
80     struct IRQState *irq = opaque;
81 
82     irq->handler(irq->opaque, irq->n, !level);
83 }
84 
85 qemu_irq qemu_irq_invert(qemu_irq irq)
86 {
87     /* The default state for IRQs is low, so raise the output now.  */
88     qemu_irq_raise(irq);
89     return qemu_allocate_irqs(qemu_notirq, irq, 1)[0];
90 }
91 
92 static void qemu_splitirq(void *opaque, int line, int level)
93 {
94     struct IRQState **irq = opaque;
95     irq[0]->handler(irq[0]->opaque, irq[0]->n, level);
96     irq[1]->handler(irq[1]->opaque, irq[1]->n, level);
97 }
98 
99 qemu_irq qemu_irq_split(qemu_irq irq1, qemu_irq irq2)
100 {
101     qemu_irq *s = g_malloc0(2 * sizeof(qemu_irq));
102     s[0] = irq1;
103     s[1] = irq2;
104     return qemu_allocate_irqs(qemu_splitirq, s, 1)[0];
105 }
106 
107 static void proxy_irq_handler(void *opaque, int n, int level)
108 {
109     qemu_irq **target = opaque;
110 
111     if (*target) {
112         qemu_set_irq((*target)[n], level);
113     }
114 }
115 
116 qemu_irq *qemu_irq_proxy(qemu_irq **target, int n)
117 {
118     return qemu_allocate_irqs(proxy_irq_handler, target, n);
119 }
120 
121 void qemu_irq_intercept_in(qemu_irq *gpio_in, qemu_irq_handler handler, int n)
122 {
123     int i;
124     qemu_irq *old_irqs = qemu_allocate_irqs(NULL, NULL, n);
125     for (i = 0; i < n; i++) {
126         *old_irqs[i] = *gpio_in[i];
127         gpio_in[i]->handler = handler;
128         gpio_in[i]->opaque = old_irqs;
129     }
130 }
131 
132 void qemu_irq_intercept_out(qemu_irq **gpio_out, qemu_irq_handler handler, int n)
133 {
134     qemu_irq *old_irqs = *gpio_out;
135     *gpio_out = qemu_allocate_irqs(handler, old_irqs, n);
136 }
137