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-rw-r--r--hw/timer/grlib_gptimer.c404
1 files changed, 404 insertions, 0 deletions
diff --git a/hw/timer/grlib_gptimer.c b/hw/timer/grlib_gptimer.c
new file mode 100644
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--- /dev/null
+++ b/hw/timer/grlib_gptimer.c
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+/*
+ * QEMU GRLIB GPTimer Emulator
+ *
+ * Copyright (c) 2010-2011 AdaCore
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy
+ * of this software and associated documentation files (the "Software"), to deal
+ * in the Software without restriction, including without limitation the rights
+ * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+ * copies of the Software, and to permit persons to whom the Software is
+ * furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in
+ * all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
+ * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+ * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
+ * THE SOFTWARE.
+ */
+
+#include "hw/sysbus.h"
+#include "qemu/timer.h"
+#include "hw/ptimer.h"
+
+#include "trace.h"
+
+#define UNIT_REG_SIZE 16 /* Size of memory mapped regs for the unit */
+#define GPTIMER_REG_SIZE 16 /* Size of memory mapped regs for a GPTimer */
+
+#define GPTIMER_MAX_TIMERS 8
+
+/* GPTimer Config register fields */
+#define GPTIMER_ENABLE (1 << 0)
+#define GPTIMER_RESTART (1 << 1)
+#define GPTIMER_LOAD (1 << 2)
+#define GPTIMER_INT_ENABLE (1 << 3)
+#define GPTIMER_INT_PENDING (1 << 4)
+#define GPTIMER_CHAIN (1 << 5) /* Not supported */
+#define GPTIMER_DEBUG_HALT (1 << 6) /* Not supported */
+
+/* Memory mapped register offsets */
+#define SCALER_OFFSET 0x00
+#define SCALER_RELOAD_OFFSET 0x04
+#define CONFIG_OFFSET 0x08
+#define COUNTER_OFFSET 0x00
+#define COUNTER_RELOAD_OFFSET 0x04
+#define TIMER_BASE 0x10
+
+typedef struct GPTimer GPTimer;
+typedef struct GPTimerUnit GPTimerUnit;
+
+struct GPTimer {
+ QEMUBH *bh;
+ struct ptimer_state *ptimer;
+
+ qemu_irq irq;
+ int id;
+ GPTimerUnit *unit;
+
+ /* registers */
+ uint32_t counter;
+ uint32_t reload;
+ uint32_t config;
+};
+
+struct GPTimerUnit {
+ SysBusDevice busdev;
+ MemoryRegion iomem;
+
+ uint32_t nr_timers; /* Number of timers available */
+ uint32_t freq_hz; /* System frequency */
+ uint32_t irq_line; /* Base irq line */
+
+ GPTimer *timers;
+
+ /* registers */
+ uint32_t scaler;
+ uint32_t reload;
+ uint32_t config;
+};
+
+static void grlib_gptimer_enable(GPTimer *timer)
+{
+ assert(timer != NULL);
+
+
+ ptimer_stop(timer->ptimer);
+
+ if (!(timer->config & GPTIMER_ENABLE)) {
+ /* Timer disabled */
+ trace_grlib_gptimer_disabled(timer->id, timer->config);
+ return;
+ }
+
+ /* ptimer is triggered when the counter reach 0 but GPTimer is triggered at
+ underflow. Set count + 1 to simulate the GPTimer behavior. */
+
+ trace_grlib_gptimer_enable(timer->id, timer->counter + 1);
+
+ ptimer_set_count(timer->ptimer, timer->counter + 1);
+ ptimer_run(timer->ptimer, 1);
+}
+
+static void grlib_gptimer_restart(GPTimer *timer)
+{
+ assert(timer != NULL);
+
+ trace_grlib_gptimer_restart(timer->id, timer->reload);
+
+ timer->counter = timer->reload;
+ grlib_gptimer_enable(timer);
+}
+
+static void grlib_gptimer_set_scaler(GPTimerUnit *unit, uint32_t scaler)
+{
+ int i = 0;
+ uint32_t value = 0;
+
+ assert(unit != NULL);
+
+ if (scaler > 0) {
+ value = unit->freq_hz / (scaler + 1);
+ } else {
+ value = unit->freq_hz;
+ }
+
+ trace_grlib_gptimer_set_scaler(scaler, value);
+
+ for (i = 0; i < unit->nr_timers; i++) {
+ ptimer_set_freq(unit->timers[i].ptimer, value);
+ }
+}
+
+static void grlib_gptimer_hit(void *opaque)
+{
+ GPTimer *timer = opaque;
+ assert(timer != NULL);
+
+ trace_grlib_gptimer_hit(timer->id);
+
+ /* Timer expired */
+
+ if (timer->config & GPTIMER_INT_ENABLE) {
+ /* Set the pending bit (only unset by write in the config register) */
+ timer->config |= GPTIMER_INT_PENDING;
+ qemu_irq_pulse(timer->irq);
+ }
+
+ if (timer->config & GPTIMER_RESTART) {
+ grlib_gptimer_restart(timer);
+ }
+}
+
+static uint64_t grlib_gptimer_read(void *opaque, hwaddr addr,
+ unsigned size)
+{
+ GPTimerUnit *unit = opaque;
+ hwaddr timer_addr;
+ int id;
+ uint32_t value = 0;
+
+ addr &= 0xff;
+
+ /* Unit registers */
+ switch (addr) {
+ case SCALER_OFFSET:
+ trace_grlib_gptimer_readl(-1, addr, unit->scaler);
+ return unit->scaler;
+
+ case SCALER_RELOAD_OFFSET:
+ trace_grlib_gptimer_readl(-1, addr, unit->reload);
+ return unit->reload;
+
+ case CONFIG_OFFSET:
+ trace_grlib_gptimer_readl(-1, addr, unit->config);
+ return unit->config;
+
+ default:
+ break;
+ }
+
+ timer_addr = (addr % TIMER_BASE);
+ id = (addr - TIMER_BASE) / TIMER_BASE;
+
+ if (id >= 0 && id < unit->nr_timers) {
+
+ /* GPTimer registers */
+ switch (timer_addr) {
+ case COUNTER_OFFSET:
+ value = ptimer_get_count(unit->timers[id].ptimer);
+ trace_grlib_gptimer_readl(id, addr, value);
+ return value;
+
+ case COUNTER_RELOAD_OFFSET:
+ value = unit->timers[id].reload;
+ trace_grlib_gptimer_readl(id, addr, value);
+ return value;
+
+ case CONFIG_OFFSET:
+ trace_grlib_gptimer_readl(id, addr, unit->timers[id].config);
+ return unit->timers[id].config;
+
+ default:
+ break;
+ }
+
+ }
+
+ trace_grlib_gptimer_readl(-1, addr, 0);
+ return 0;
+}
+
+static void grlib_gptimer_write(void *opaque, hwaddr addr,
+ uint64_t value, unsigned size)
+{
+ GPTimerUnit *unit = opaque;
+ hwaddr timer_addr;
+ int id;
+
+ addr &= 0xff;
+
+ /* Unit registers */
+ switch (addr) {
+ case SCALER_OFFSET:
+ value &= 0xFFFF; /* clean up the value */
+ unit->scaler = value;
+ trace_grlib_gptimer_writel(-1, addr, unit->scaler);
+ return;
+
+ case SCALER_RELOAD_OFFSET:
+ value &= 0xFFFF; /* clean up the value */
+ unit->reload = value;
+ trace_grlib_gptimer_writel(-1, addr, unit->reload);
+ grlib_gptimer_set_scaler(unit, value);
+ return;
+
+ case CONFIG_OFFSET:
+ /* Read Only (disable timer freeze not supported) */
+ trace_grlib_gptimer_writel(-1, addr, 0);
+ return;
+
+ default:
+ break;
+ }
+
+ timer_addr = (addr % TIMER_BASE);
+ id = (addr - TIMER_BASE) / TIMER_BASE;
+
+ if (id >= 0 && id < unit->nr_timers) {
+
+ /* GPTimer registers */
+ switch (timer_addr) {
+ case COUNTER_OFFSET:
+ trace_grlib_gptimer_writel(id, addr, value);
+ unit->timers[id].counter = value;
+ grlib_gptimer_enable(&unit->timers[id]);
+ return;
+
+ case COUNTER_RELOAD_OFFSET:
+ trace_grlib_gptimer_writel(id, addr, value);
+ unit->timers[id].reload = value;
+ return;
+
+ case CONFIG_OFFSET:
+ trace_grlib_gptimer_writel(id, addr, value);
+
+ if (value & GPTIMER_INT_PENDING) {
+ /* clear pending bit */
+ value &= ~GPTIMER_INT_PENDING;
+ } else {
+ /* keep pending bit */
+ value |= unit->timers[id].config & GPTIMER_INT_PENDING;
+ }
+
+ unit->timers[id].config = value;
+
+ /* gptimer_restart calls gptimer_enable, so if "enable" and "load"
+ bits are present, we just have to call restart. */
+
+ if (value & GPTIMER_LOAD) {
+ grlib_gptimer_restart(&unit->timers[id]);
+ } else if (value & GPTIMER_ENABLE) {
+ grlib_gptimer_enable(&unit->timers[id]);
+ }
+
+ /* These fields must always be read as 0 */
+ value &= ~(GPTIMER_LOAD & GPTIMER_DEBUG_HALT);
+
+ unit->timers[id].config = value;
+ return;
+
+ default:
+ break;
+ }
+
+ }
+
+ trace_grlib_gptimer_writel(-1, addr, value);
+}
+
+static const MemoryRegionOps grlib_gptimer_ops = {
+ .read = grlib_gptimer_read,
+ .write = grlib_gptimer_write,
+ .endianness = DEVICE_NATIVE_ENDIAN,
+ .valid = {
+ .min_access_size = 4,
+ .max_access_size = 4,
+ },
+};
+
+static void grlib_gptimer_reset(DeviceState *d)
+{
+ GPTimerUnit *unit = container_of(d, GPTimerUnit, busdev.qdev);
+ int i = 0;
+
+ assert(unit != NULL);
+
+ unit->scaler = 0;
+ unit->reload = 0;
+ unit->config = 0;
+
+ unit->config = unit->nr_timers;
+ unit->config |= unit->irq_line << 3;
+ unit->config |= 1 << 8; /* separate interrupt */
+ unit->config |= 1 << 9; /* Disable timer freeze */
+
+
+ for (i = 0; i < unit->nr_timers; i++) {
+ GPTimer *timer = &unit->timers[i];
+
+ timer->counter = 0;
+ timer->reload = 0;
+ timer->config = 0;
+ ptimer_stop(timer->ptimer);
+ ptimer_set_count(timer->ptimer, 0);
+ ptimer_set_freq(timer->ptimer, unit->freq_hz);
+ }
+}
+
+static int grlib_gptimer_init(SysBusDevice *dev)
+{
+ GPTimerUnit *unit = FROM_SYSBUS(typeof(*unit), dev);
+ unsigned int i;
+
+ assert(unit->nr_timers > 0);
+ assert(unit->nr_timers <= GPTIMER_MAX_TIMERS);
+
+ unit->timers = g_malloc0(sizeof unit->timers[0] * unit->nr_timers);
+
+ for (i = 0; i < unit->nr_timers; i++) {
+ GPTimer *timer = &unit->timers[i];
+
+ timer->unit = unit;
+ timer->bh = qemu_bh_new(grlib_gptimer_hit, timer);
+ timer->ptimer = ptimer_init(timer->bh);
+ timer->id = i;
+
+ /* One IRQ line for each timer */
+ sysbus_init_irq(dev, &timer->irq);
+
+ ptimer_set_freq(timer->ptimer, unit->freq_hz);
+ }
+
+ memory_region_init_io(&unit->iomem, &grlib_gptimer_ops, unit, "gptimer",
+ UNIT_REG_SIZE + GPTIMER_REG_SIZE * unit->nr_timers);
+
+ sysbus_init_mmio(dev, &unit->iomem);
+ return 0;
+}
+
+static Property grlib_gptimer_properties[] = {
+ DEFINE_PROP_UINT32("frequency", GPTimerUnit, freq_hz, 40000000),
+ DEFINE_PROP_UINT32("irq-line", GPTimerUnit, irq_line, 8),
+ DEFINE_PROP_UINT32("nr-timers", GPTimerUnit, nr_timers, 2),
+ DEFINE_PROP_END_OF_LIST(),
+};
+
+static void grlib_gptimer_class_init(ObjectClass *klass, void *data)
+{
+ DeviceClass *dc = DEVICE_CLASS(klass);
+ SysBusDeviceClass *k = SYS_BUS_DEVICE_CLASS(klass);
+
+ k->init = grlib_gptimer_init;
+ dc->reset = grlib_gptimer_reset;
+ dc->props = grlib_gptimer_properties;
+}
+
+static const TypeInfo grlib_gptimer_info = {
+ .name = "grlib,gptimer",
+ .parent = TYPE_SYS_BUS_DEVICE,
+ .instance_size = sizeof(GPTimerUnit),
+ .class_init = grlib_gptimer_class_init,
+};
+
+static void grlib_gptimer_register_types(void)
+{
+ type_register_static(&grlib_gptimer_info);
+}
+
+type_init(grlib_gptimer_register_types)