LXR qemu/hw/nios2/cpu

   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 "qemu-common.h"
  23#include "cpu.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    Nios2CPU *cpu = nios2_env_get_cpu(env);
  58    CPUState *cs = CPU(cpu);
  59
  60    if (env->irq_pending) {
  61        env->irq_pending = 0;
  62        cpu_interrupt(cs, CPU_INTERRUPT_HARD);
  63    }
  64}
  65
  66qemu_irq *nios2_cpu_pic_init(Nios2CPU *cpu)
  67{
  68    return qemu_allocate_irqs(nios2_pic_cpu_handler, cpu, 2);
  69}
  70