qemu-e2k/hw/xtensa/pic_cpu.c

167 lines
5.8 KiB
C

/*
* Copyright (c) 2011, Max Filippov, Open Source and Linux Lab.
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions are met:
* * Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* * Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
* * Neither the name of the Open Source and Linux Lab nor the
* names of its contributors may be used to endorse or promote products
* derived from this software without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
* AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY
* DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
* (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
* LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
* ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
* (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
* SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*/
#include "hw/hw.h"
#include "qemu/log.h"
#include "qemu/timer.h"
void xtensa_advance_ccount(CPUXtensaState *env, uint32_t d)
{
uint32_t old_ccount = env->sregs[CCOUNT] + 1;
env->sregs[CCOUNT] += d;
if (xtensa_option_enabled(env->config, XTENSA_OPTION_TIMER_INTERRUPT)) {
int i;
for (i = 0; i < env->config->nccompare; ++i) {
if (env->sregs[CCOMPARE + i] - old_ccount < d) {
xtensa_timer_irq(env, i, 1);
}
}
}
}
void check_interrupts(CPUXtensaState *env)
{
CPUState *cs = CPU(xtensa_env_get_cpu(env));
int minlevel = xtensa_get_cintlevel(env);
uint32_t int_set_enabled = env->sregs[INTSET] & env->sregs[INTENABLE];
int level;
/* If the CPU is halted advance CCOUNT according to the QEMU_CLOCK_VIRTUAL time
* elapsed since the moment when it was advanced last time.
*/
if (cs->halted) {
int64_t now = qemu_clock_get_ns(QEMU_CLOCK_VIRTUAL);
xtensa_advance_ccount(env,
muldiv64(now - env->halt_clock,
env->config->clock_freq_khz, 1000000));
env->halt_clock = now;
}
for (level = env->config->nlevel; level > minlevel; --level) {
if (env->config->level_mask[level] & int_set_enabled) {
env->pending_irq_level = level;
cpu_interrupt(cs, CPU_INTERRUPT_HARD);
qemu_log_mask(CPU_LOG_INT,
"%s level = %d, cintlevel = %d, "
"pc = %08x, a0 = %08x, ps = %08x, "
"intset = %08x, intenable = %08x, "
"ccount = %08x\n",
__func__, level, xtensa_get_cintlevel(env),
env->pc, env->regs[0], env->sregs[PS],
env->sregs[INTSET], env->sregs[INTENABLE],
env->sregs[CCOUNT]);
return;
}
}
env->pending_irq_level = 0;
cpu_reset_interrupt(cs, CPU_INTERRUPT_HARD);
}
static void xtensa_set_irq(void *opaque, int irq, int active)
{
CPUXtensaState *env = opaque;
if (irq >= env->config->ninterrupt) {
qemu_log("%s: bad IRQ %d\n", __func__, irq);
} else {
uint32_t irq_bit = 1 << irq;
if (active) {
env->sregs[INTSET] |= irq_bit;
} else if (env->config->interrupt[irq].inttype == INTTYPE_LEVEL) {
env->sregs[INTSET] &= ~irq_bit;
}
check_interrupts(env);
}
}
void xtensa_timer_irq(CPUXtensaState *env, uint32_t id, uint32_t active)
{
qemu_set_irq(env->irq_inputs[env->config->timerint[id]], active);
}
void xtensa_rearm_ccompare_timer(CPUXtensaState *env)
{
int i;
uint32_t wake_ccount = env->sregs[CCOUNT] - 1;
for (i = 0; i < env->config->nccompare; ++i) {
if (env->sregs[CCOMPARE + i] - env->sregs[CCOUNT] <
wake_ccount - env->sregs[CCOUNT]) {
wake_ccount = env->sregs[CCOMPARE + i];
}
}
env->wake_ccount = wake_ccount;
timer_mod(env->ccompare_timer, env->halt_clock +
muldiv64(wake_ccount - env->sregs[CCOUNT],
1000000, env->config->clock_freq_khz));
}
static void xtensa_ccompare_cb(void *opaque)
{
XtensaCPU *cpu = opaque;
CPUXtensaState *env = &cpu->env;
CPUState *cs = CPU(cpu);
if (cs->halted) {
env->halt_clock = qemu_clock_get_ns(QEMU_CLOCK_VIRTUAL);
xtensa_advance_ccount(env, env->wake_ccount - env->sregs[CCOUNT]);
if (!cpu_has_work(cs)) {
env->sregs[CCOUNT] = env->wake_ccount + 1;
xtensa_rearm_ccompare_timer(env);
}
}
}
void xtensa_irq_init(CPUXtensaState *env)
{
XtensaCPU *cpu = xtensa_env_get_cpu(env);
env->irq_inputs = (void **)qemu_allocate_irqs(
xtensa_set_irq, env, env->config->ninterrupt);
if (xtensa_option_enabled(env->config, XTENSA_OPTION_TIMER_INTERRUPT) &&
env->config->nccompare > 0) {
env->ccompare_timer =
timer_new_ns(QEMU_CLOCK_VIRTUAL, &xtensa_ccompare_cb, cpu);
}
}
void *xtensa_get_extint(CPUXtensaState *env, unsigned extint)
{
if (extint < env->config->nextint) {
unsigned irq = env->config->extint[extint];
return env->irq_inputs[irq];
} else {
qemu_log("%s: trying to acquire invalid external interrupt %d\n",
__func__, extint);
return NULL;
}
}