qemu-e2k/hw/nios2/cpu_pic.c

70 lines
1.9 KiB
C
Raw Normal View History

/*
* Altera Nios2 CPU PIC
*
* Copyright (c) 2016 Marek Vasut <marek.vasut@gmail.com>
*
* This library is free software; you can redistribute it and/or
* modify it under the terms of the GNU Lesser General Public
* License as published by the Free Software Foundation; either
* version 2.1 of the License, or (at your option) any later version.
*
* This library is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* Lesser General Public License for more details.
*
* You should have received a copy of the GNU Lesser General Public
* License along with this library; if not, see
* <http://www.gnu.org/licenses/lgpl-2.1.html>
*/
#include "qemu/osdep.h"
#include "qemu-common.h"
#include "cpu.h"
#include "qemu/config-file.h"
#include "boot.h"
static void nios2_pic_cpu_handler(void *opaque, int irq, int level)
{
Nios2CPU *cpu = opaque;
CPUNios2State *env = &cpu->env;
CPUState *cs = CPU(cpu);
int type = irq ? CPU_INTERRUPT_NMI : CPU_INTERRUPT_HARD;
if (type == CPU_INTERRUPT_HARD) {
env->irq_pending = level;
if (level && (env->regs[CR_STATUS] & CR_STATUS_PIE)) {
env->irq_pending = 0;
cpu_interrupt(cs, type);
} else if (!level) {
env->irq_pending = 0;
cpu_reset_interrupt(cs, type);
}
} else {
if (level) {
cpu_interrupt(cs, type);
} else {
cpu_reset_interrupt(cs, type);
}
}
}
void nios2_check_interrupts(CPUNios2State *env)
{
Nios2CPU *cpu = nios2_env_get_cpu(env);
CPUState *cs = CPU(cpu);
if (env->irq_pending) {
env->irq_pending = 0;
cpu_interrupt(cs, CPU_INTERRUPT_HARD);
}
}
qemu_irq *nios2_cpu_pic_init(Nios2CPU *cpu)
{
return qemu_allocate_irqs(nios2_pic_cpu_handler, cpu, 2);
}