hw/irq.c

   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 "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 }