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-rw-r--r--hw/xtensa/pic_cpu.c164
1 files changed, 164 insertions, 0 deletions
diff --git a/hw/xtensa/pic_cpu.c b/hw/xtensa/pic_cpu.c
new file mode 100644
index 0000000000..f485a1465c
--- /dev/null
+++ b/hw/xtensa/pic_cpu.c
@@ -0,0 +1,164 @@
+/*
+ * 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];
+
+ 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)
+{
+ 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 vm_clock time
+ * elapsed since the moment when it was advanced last time.
+ */
+ if (env->halted) {
+ int64_t now = qemu_get_clock_ns(vm_clock);
+
+ 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(env, 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(env, 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;
+ qemu_mod_timer(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;
+
+ if (env->halted) {
+ env->halt_clock = qemu_get_clock_ns(vm_clock);
+ xtensa_advance_ccount(env, env->wake_ccount - env->sregs[CCOUNT]);
+ if (!cpu_has_work(CPU(cpu))) {
+ 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 =
+ qemu_new_timer_ns(vm_clock, &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;
+ }
+}