1/*
2 * Altera Nios2 CPU PIC
3 *
4 * Copyright (c) 2016 Marek Vasut <marek.vasut@gmail.com>
5 *
6 * This library is free software; you can redistribute it and/or
7 * modify it under the terms of the GNU Lesser General Public
8 * License as published by the Free Software Foundation; either
9 * version 2.1 of the License, or (at your option) any later version.
10 *
11 * This library is distributed in the hope that it will be useful,
12 * but WITHOUT ANY WARRANTY; without even the implied warranty of
13 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
14 * Lesser General Public License for more details.
15 *
16 * You should have received a copy of the GNU Lesser General Public
17 * License along with this library; if not, see
18 * <http://www.gnu.org/licenses/lgpl-2.1.html>
19 */
20
21#include "qemu/osdep.h"
22#include "cpu.h"
23#include "hw/irq.h"
24
25#include "qemu/config-file.h"
26
27#include "boot.h"
28
29static void nios2_pic_cpu_handler(void *opaque, int irq, int level)
30{
31 Nios2CPU *cpu = opaque;
32 CPUNios2State *env = &cpu->env;
33 CPUState *cs = CPU(cpu);
34 int type = irq ? CPU_INTERRUPT_NMI : CPU_INTERRUPT_HARD;
35
36 if (type == CPU_INTERRUPT_HARD) {
37 env->irq_pending = level;
38
39 if (level && (env->regs[CR_STATUS] & CR_STATUS_PIE)) {
40 env->irq_pending = 0;
41 cpu_interrupt(cs, type);
42 } else if (!level) {
43 env->irq_pending = 0;
44 cpu_reset_interrupt(cs, type);
45 }
46 } else {
47 if (level) {
48 cpu_interrupt(cs, type);
49 } else {
50 cpu_reset_interrupt(cs, type);
51 }
52 }
53}
54
55void nios2_check_interrupts(CPUNios2State *env)
56{
57 if (env->irq_pending) {
58 env->irq_pending = 0;
59 cpu_interrupt(env_cpu(env), CPU_INTERRUPT_HARD);
60 }
61}
62
63qemu_irq *nios2_cpu_pic_init(Nios2CPU *cpu)
64{
65 return qemu_allocate_irqs(nios2_pic_cpu_handler, cpu, 2);
66}
67