--- /dev/null
+/*
+ * QEMU model of the LatticeMico32 timer block.
+ *
+ * Copyright (c) 2010 Michael Walle <michael@walle.cc>
+ *
+ * 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 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/>.
+ *
+ *
+ * Specification available at:
+ * http://www.latticesemi.com/documents/mico32timer.pdf
+ */
+
+#include "hw/hw.h"
+#include "hw/sysbus.h"
+#include "trace.h"
+#include "qemu/timer.h"
+#include "hw/ptimer.h"
+#include "qemu/error-report.h"
+#include "qemu/main-loop.h"
+
+#define DEFAULT_FREQUENCY (50*1000000)
+
+enum {
+ R_SR = 0,
+ R_CR,
+ R_PERIOD,
+ R_SNAPSHOT,
+ R_MAX
+};
+
+enum {
+ SR_TO = (1 << 0),
+ SR_RUN = (1 << 1),
+};
+
+enum {
+ CR_ITO = (1 << 0),
+ CR_CONT = (1 << 1),
+ CR_START = (1 << 2),
+ CR_STOP = (1 << 3),
+};
+
+#define TYPE_LM32_TIMER "lm32-timer"
+#define LM32_TIMER(obj) OBJECT_CHECK(LM32TimerState, (obj), TYPE_LM32_TIMER)
+
+struct LM32TimerState {
+ SysBusDevice parent_obj;
+
+ MemoryRegion iomem;
+
+ QEMUBH *bh;
+ ptimer_state *ptimer;
+
+ qemu_irq irq;
+ uint32_t freq_hz;
+
+ uint32_t regs[R_MAX];
+};
+typedef struct LM32TimerState LM32TimerState;
+
+static void timer_update_irq(LM32TimerState *s)
+{
+ int state = (s->regs[R_SR] & SR_TO) && (s->regs[R_CR] & CR_ITO);
+
+ trace_lm32_timer_irq_state(state);
+ qemu_set_irq(s->irq, state);
+}
+
+static uint64_t timer_read(void *opaque, hwaddr addr, unsigned size)
+{
+ LM32TimerState *s = opaque;
+ uint32_t r = 0;
+
+ addr >>= 2;
+ switch (addr) {
+ case R_SR:
+ case R_CR:
+ case R_PERIOD:
+ r = s->regs[addr];
+ break;
+ case R_SNAPSHOT:
+ r = (uint32_t)ptimer_get_count(s->ptimer);
+ break;
+ default:
+ error_report("lm32_timer: read access to unknown register 0x"
+ TARGET_FMT_plx, addr << 2);
+ break;
+ }
+
+ trace_lm32_timer_memory_read(addr << 2, r);
+ return r;
+}
+
+static void timer_write(void *opaque, hwaddr addr,
+ uint64_t value, unsigned size)
+{
+ LM32TimerState *s = opaque;
+
+ trace_lm32_timer_memory_write(addr, value);
+
+ addr >>= 2;
+ switch (addr) {
+ case R_SR:
+ s->regs[R_SR] &= ~SR_TO;
+ break;
+ case R_CR:
+ s->regs[R_CR] = value;
+ if (s->regs[R_CR] & CR_START) {
+ ptimer_run(s->ptimer, 1);
+ }
+ if (s->regs[R_CR] & CR_STOP) {
+ ptimer_stop(s->ptimer);
+ }
+ break;
+ case R_PERIOD:
+ s->regs[R_PERIOD] = value;
+ ptimer_set_count(s->ptimer, value);
+ break;
+ case R_SNAPSHOT:
+ error_report("lm32_timer: write access to read only register 0x"
+ TARGET_FMT_plx, addr << 2);
+ break;
+ default:
+ error_report("lm32_timer: write access to unknown register 0x"
+ TARGET_FMT_plx, addr << 2);
+ break;
+ }
+ timer_update_irq(s);
+}
+
+static const MemoryRegionOps timer_ops = {
+ .read = timer_read,
+ .write = timer_write,
+ .endianness = DEVICE_NATIVE_ENDIAN,
+ .valid = {
+ .min_access_size = 4,
+ .max_access_size = 4,
+ },
+};
+
+static void timer_hit(void *opaque)
+{
+ LM32TimerState *s = opaque;
+
+ trace_lm32_timer_hit();
+
+ s->regs[R_SR] |= SR_TO;
+
+ if (s->regs[R_CR] & CR_CONT) {
+ ptimer_set_count(s->ptimer, s->regs[R_PERIOD]);
+ ptimer_run(s->ptimer, 1);
+ }
+ timer_update_irq(s);
+}
+
+static void timer_reset(DeviceState *d)
+{
+ LM32TimerState *s = LM32_TIMER(d);
+ int i;
+
+ for (i = 0; i < R_MAX; i++) {
+ s->regs[i] = 0;
+ }
+ ptimer_stop(s->ptimer);
+}
+
+static int lm32_timer_init(SysBusDevice *dev)
+{
+ LM32TimerState *s = LM32_TIMER(dev);
+
+ sysbus_init_irq(dev, &s->irq);
+
+ s->bh = qemu_bh_new(timer_hit, s);
+ s->ptimer = ptimer_init(s->bh);
+ ptimer_set_freq(s->ptimer, s->freq_hz);
+
+ memory_region_init_io(&s->iomem, OBJECT(s), &timer_ops, s,
+ "timer", R_MAX * 4);
+ sysbus_init_mmio(dev, &s->iomem);
+
+ return 0;
+}
+
+static const VMStateDescription vmstate_lm32_timer = {
+ .name = "lm32-timer",
+ .version_id = 1,
+ .minimum_version_id = 1,
+ .fields = (VMStateField[]) {
+ VMSTATE_PTIMER(ptimer, LM32TimerState),
+ VMSTATE_UINT32(freq_hz, LM32TimerState),
+ VMSTATE_UINT32_ARRAY(regs, LM32TimerState, R_MAX),
+ VMSTATE_END_OF_LIST()
+ }
+};
+
+static Property lm32_timer_properties[] = {
+ DEFINE_PROP_UINT32("frequency", LM32TimerState, freq_hz, DEFAULT_FREQUENCY),
+ DEFINE_PROP_END_OF_LIST(),
+};
+
+static void lm32_timer_class_init(ObjectClass *klass, void *data)
+{
+ DeviceClass *dc = DEVICE_CLASS(klass);
+ SysBusDeviceClass *k = SYS_BUS_DEVICE_CLASS(klass);
+
+ k->init = lm32_timer_init;
+ dc->reset = timer_reset;
+ dc->vmsd = &vmstate_lm32_timer;
+ dc->props = lm32_timer_properties;
+}
+
+static const TypeInfo lm32_timer_info = {
+ .name = TYPE_LM32_TIMER,
+ .parent = TYPE_SYS_BUS_DEVICE,
+ .instance_size = sizeof(LM32TimerState),
+ .class_init = lm32_timer_class_init,
+};
+
+static void lm32_timer_register_types(void)
+{
+ type_register_static(&lm32_timer_info);
+}
+
+type_init(lm32_timer_register_types)
Code Review / kvmfornfv.git / blobdiff