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-rw-r--r--hw/timer/Makefile.objs1
-rw-r--r--hw/timer/nrf51_timer.c393
-rw-r--r--hw/timer/trace-events5
3 files changed, 399 insertions, 0 deletions
diff --git a/hw/timer/Makefile.objs b/hw/timer/Makefile.objs
index b32194d153..0e9a4530f8 100644
--- a/hw/timer/Makefile.objs
+++ b/hw/timer/Makefile.objs
@@ -23,6 +23,7 @@ common-obj-$(CONFIG_IMX) += imx_gpt.o
common-obj-$(CONFIG_LM32) += lm32_timer.o
common-obj-$(CONFIG_MILKYMIST) += milkymist-sysctl.o
common-obj-$(CONFIG_XLNX_ZYNQMP) += xlnx-zynqmp-rtc.o
+common-obj-$(CONFIG_NRF51_SOC) += nrf51_timer.o
obj-$(CONFIG_ALTERA_TIMER) += altera_timer.o
obj-$(CONFIG_EXYNOS4) += exynos4210_mct.o
diff --git a/hw/timer/nrf51_timer.c b/hw/timer/nrf51_timer.c
new file mode 100644
index 0000000000..0c90662896
--- /dev/null
+++ b/hw/timer/nrf51_timer.c
@@ -0,0 +1,393 @@
+/*
+ * nRF51 System-on-Chip Timer peripheral
+ *
+ * Reference Manual: http://infocenter.nordicsemi.com/pdf/nRF51_RM_v3.0.pdf
+ * Product Spec: http://infocenter.nordicsemi.com/pdf/nRF51822_PS_v3.1.pdf
+ *
+ * Copyright 2018 Steffen Görtz <contrib@steffen-goertz.de>
+ * Copyright (c) 2019 Red Hat, Inc.
+ *
+ * This code is licensed under the GPL version 2 or later. See
+ * the COPYING file in the top-level directory.
+ */
+
+#include "qemu/osdep.h"
+#include "qemu/log.h"
+#include "hw/arm/nrf51.h"
+#include "hw/timer/nrf51_timer.h"
+#include "trace.h"
+
+#define TIMER_CLK_FREQ 16000000UL
+
+static uint32_t const bitwidths[] = {16, 8, 24, 32};
+
+static uint32_t ns_to_ticks(NRF51TimerState *s, int64_t ns)
+{
+ uint32_t freq = TIMER_CLK_FREQ >> s->prescaler;
+
+ return muldiv64(ns, freq, NANOSECONDS_PER_SECOND);
+}
+
+static int64_t ticks_to_ns(NRF51TimerState *s, uint32_t ticks)
+{
+ uint32_t freq = TIMER_CLK_FREQ >> s->prescaler;
+
+ return muldiv64(ticks, NANOSECONDS_PER_SECOND, freq);
+}
+
+/* Returns number of ticks since last call */
+static uint32_t update_counter(NRF51TimerState *s, int64_t now)
+{
+ uint32_t ticks = ns_to_ticks(s, now - s->update_counter_ns);
+
+ s->counter = (s->counter + ticks) % BIT(bitwidths[s->bitmode]);
+ s->update_counter_ns = now;
+ return ticks;
+}
+
+/* Assumes s->counter is up-to-date */
+static void rearm_timer(NRF51TimerState *s, int64_t now)
+{
+ int64_t min_ns = INT64_MAX;
+ size_t i;
+
+ for (i = 0; i < NRF51_TIMER_REG_COUNT; i++) {
+ int64_t delta_ns;
+
+ if (s->events_compare[i]) {
+ continue; /* already expired, ignore it for now */
+ }
+
+ if (s->cc[i] <= s->counter) {
+ delta_ns = ticks_to_ns(s, BIT(bitwidths[s->bitmode]) -
+ s->counter + s->cc[i]);
+ } else {
+ delta_ns = ticks_to_ns(s, s->cc[i] - s->counter);
+ }
+
+ if (delta_ns < min_ns) {
+ min_ns = delta_ns;
+ }
+ }
+
+ if (min_ns != INT64_MAX) {
+ timer_mod_ns(&s->timer, now + min_ns);
+ }
+}
+
+static void update_irq(NRF51TimerState *s)
+{
+ bool flag = false;
+ size_t i;
+
+ for (i = 0; i < NRF51_TIMER_REG_COUNT; i++) {
+ flag |= s->events_compare[i] && extract32(s->inten, 16 + i, 1);
+ }
+ qemu_set_irq(s->irq, flag);
+}
+
+static void timer_expire(void *opaque)
+{
+ NRF51TimerState *s = NRF51_TIMER(opaque);
+ int64_t now = qemu_clock_get_ns(QEMU_CLOCK_VIRTUAL);
+ uint32_t cc_remaining[NRF51_TIMER_REG_COUNT];
+ bool should_stop = false;
+ uint32_t ticks;
+ size_t i;
+
+ for (i = 0; i < NRF51_TIMER_REG_COUNT; i++) {
+ if (s->cc[i] > s->counter) {
+ cc_remaining[i] = s->cc[i] - s->counter;
+ } else {
+ cc_remaining[i] = BIT(bitwidths[s->bitmode]) -
+ s->counter + s->cc[i];
+ }
+ }
+
+ ticks = update_counter(s, now);
+
+ for (i = 0; i < NRF51_TIMER_REG_COUNT; i++) {
+ if (cc_remaining[i] <= ticks) {
+ s->events_compare[i] = 1;
+
+ if (s->shorts & BIT(i)) {
+ s->timer_start_ns = now;
+ s->update_counter_ns = s->timer_start_ns;
+ s->counter = 0;
+ }
+
+ should_stop |= s->shorts & BIT(i + 8);
+ }
+ }
+
+ update_irq(s);
+
+ if (should_stop) {
+ s->running = false;
+ timer_del(&s->timer);
+ } else {
+ rearm_timer(s, now);
+ }
+}
+
+static void counter_compare(NRF51TimerState *s)
+{
+ uint32_t counter = s->counter;
+ size_t i;
+
+ for (i = 0; i < NRF51_TIMER_REG_COUNT; i++) {
+ if (counter == s->cc[i]) {
+ s->events_compare[i] = 1;
+
+ if (s->shorts & BIT(i)) {
+ s->counter = 0;
+ }
+ }
+ }
+}
+
+static uint64_t nrf51_timer_read(void *opaque, hwaddr offset, unsigned int size)
+{
+ NRF51TimerState *s = NRF51_TIMER(opaque);
+ uint64_t r = 0;
+
+ switch (offset) {
+ case NRF51_TIMER_EVENT_COMPARE_0 ... NRF51_TIMER_EVENT_COMPARE_3:
+ r = s->events_compare[(offset - NRF51_TIMER_EVENT_COMPARE_0) / 4];
+ break;
+ case NRF51_TIMER_REG_SHORTS:
+ r = s->shorts;
+ break;
+ case NRF51_TIMER_REG_INTENSET:
+ r = s->inten;
+ break;
+ case NRF51_TIMER_REG_INTENCLR:
+ r = s->inten;
+ break;
+ case NRF51_TIMER_REG_MODE:
+ r = s->mode;
+ break;
+ case NRF51_TIMER_REG_BITMODE:
+ r = s->bitmode;
+ break;
+ case NRF51_TIMER_REG_PRESCALER:
+ r = s->prescaler;
+ break;
+ case NRF51_TIMER_REG_CC0 ... NRF51_TIMER_REG_CC3:
+ r = s->cc[(offset - NRF51_TIMER_REG_CC0) / 4];
+ break;
+ default:
+ qemu_log_mask(LOG_GUEST_ERROR,
+ "%s: bad read offset 0x%" HWADDR_PRIx "\n",
+ __func__, offset);
+ }
+
+ trace_nrf51_timer_read(offset, r, size);
+
+ return r;
+}
+
+static void nrf51_timer_write(void *opaque, hwaddr offset,
+ uint64_t value, unsigned int size)
+{
+ NRF51TimerState *s = NRF51_TIMER(opaque);
+ uint64_t now = qemu_clock_get_ns(QEMU_CLOCK_VIRTUAL);
+ size_t idx;
+
+ trace_nrf51_timer_write(offset, value, size);
+
+ switch (offset) {
+ case NRF51_TIMER_TASK_START:
+ if (value == NRF51_TRIGGER_TASK && s->mode == NRF51_TIMER_TIMER) {
+ s->running = true;
+ s->timer_start_ns = now - ticks_to_ns(s, s->counter);
+ s->update_counter_ns = s->timer_start_ns;
+ rearm_timer(s, now);
+ }
+ break;
+ case NRF51_TIMER_TASK_STOP:
+ case NRF51_TIMER_TASK_SHUTDOWN:
+ if (value == NRF51_TRIGGER_TASK) {
+ s->running = false;
+ timer_del(&s->timer);
+ }
+ break;
+ case NRF51_TIMER_TASK_COUNT:
+ if (value == NRF51_TRIGGER_TASK && s->mode == NRF51_TIMER_COUNTER) {
+ s->counter = (s->counter + 1) % BIT(bitwidths[s->bitmode]);
+ counter_compare(s);
+ }
+ break;
+ case NRF51_TIMER_TASK_CLEAR:
+ if (value == NRF51_TRIGGER_TASK) {
+ s->timer_start_ns = now;
+ s->update_counter_ns = s->timer_start_ns;
+ s->counter = 0;
+ if (s->running) {
+ rearm_timer(s, now);
+ }
+ }
+ break;
+ case NRF51_TIMER_TASK_CAPTURE_0 ... NRF51_TIMER_TASK_CAPTURE_3:
+ if (value == NRF51_TRIGGER_TASK) {
+ if (s->running) {
+ timer_expire(s); /* update counter and all state */
+ }
+
+ idx = (offset - NRF51_TIMER_TASK_CAPTURE_0) / 4;
+ s->cc[idx] = s->counter;
+ }
+ break;
+ case NRF51_TIMER_EVENT_COMPARE_0 ... NRF51_TIMER_EVENT_COMPARE_3:
+ if (value == NRF51_EVENT_CLEAR) {
+ s->events_compare[(offset - NRF51_TIMER_EVENT_COMPARE_0) / 4] = 0;
+
+ if (s->running) {
+ timer_expire(s); /* update counter and all state */
+ }
+ }
+ break;
+ case NRF51_TIMER_REG_SHORTS:
+ s->shorts = value & NRF51_TIMER_REG_SHORTS_MASK;
+ break;
+ case NRF51_TIMER_REG_INTENSET:
+ s->inten |= value & NRF51_TIMER_REG_INTEN_MASK;
+ break;
+ case NRF51_TIMER_REG_INTENCLR:
+ s->inten &= ~(value & NRF51_TIMER_REG_INTEN_MASK);
+ break;
+ case NRF51_TIMER_REG_MODE:
+ s->mode = value;
+ break;
+ case NRF51_TIMER_REG_BITMODE:
+ if (s->mode == NRF51_TIMER_TIMER && s->running) {
+ qemu_log_mask(LOG_GUEST_ERROR,
+ "%s: erroneous change of BITMODE while timer is running\n",
+ __func__);
+ }
+ s->bitmode = value & NRF51_TIMER_REG_BITMODE_MASK;
+ break;
+ case NRF51_TIMER_REG_PRESCALER:
+ if (s->mode == NRF51_TIMER_TIMER && s->running) {
+ qemu_log_mask(LOG_GUEST_ERROR,
+ "%s: erroneous change of PRESCALER while timer is running\n",
+ __func__);
+ }
+ s->prescaler = value & NRF51_TIMER_REG_PRESCALER_MASK;
+ break;
+ case NRF51_TIMER_REG_CC0 ... NRF51_TIMER_REG_CC3:
+ if (s->running) {
+ timer_expire(s); /* update counter */
+ }
+
+ idx = (offset - NRF51_TIMER_REG_CC0) / 4;
+ s->cc[idx] = value % BIT(bitwidths[s->bitmode]);
+
+ if (s->running) {
+ rearm_timer(s, now);
+ }
+ break;
+ default:
+ qemu_log_mask(LOG_GUEST_ERROR,
+ "%s: bad write offset 0x%" HWADDR_PRIx "\n",
+ __func__, offset);
+ }
+
+ update_irq(s);
+}
+
+static const MemoryRegionOps rng_ops = {
+ .read = nrf51_timer_read,
+ .write = nrf51_timer_write,
+ .endianness = DEVICE_LITTLE_ENDIAN,
+ .impl.min_access_size = 4,
+ .impl.max_access_size = 4,
+};
+
+static void nrf51_timer_init(Object *obj)
+{
+ NRF51TimerState *s = NRF51_TIMER(obj);
+ SysBusDevice *sbd = SYS_BUS_DEVICE(obj);
+
+ memory_region_init_io(&s->iomem, obj, &rng_ops, s,
+ TYPE_NRF51_TIMER, NRF51_TIMER_SIZE);
+ sysbus_init_mmio(sbd, &s->iomem);
+ sysbus_init_irq(sbd, &s->irq);
+
+ timer_init_ns(&s->timer, QEMU_CLOCK_VIRTUAL, timer_expire, s);
+}
+
+static void nrf51_timer_reset(DeviceState *dev)
+{
+ NRF51TimerState *s = NRF51_TIMER(dev);
+
+ timer_del(&s->timer);
+ s->timer_start_ns = 0x00;
+ s->update_counter_ns = 0x00;
+ s->counter = 0x00;
+ s->running = false;
+
+ memset(s->events_compare, 0x00, sizeof(s->events_compare));
+ memset(s->cc, 0x00, sizeof(s->cc));
+
+ s->shorts = 0x00;
+ s->inten = 0x00;
+ s->mode = 0x00;
+ s->bitmode = 0x00;
+ s->prescaler = 0x00;
+}
+
+static int nrf51_timer_post_load(void *opaque, int version_id)
+{
+ NRF51TimerState *s = NRF51_TIMER(opaque);
+
+ if (s->running && s->mode == NRF51_TIMER_TIMER) {
+ timer_expire(s);
+ }
+ return 0;
+}
+
+static const VMStateDescription vmstate_nrf51_timer = {
+ .name = TYPE_NRF51_TIMER,
+ .version_id = 1,
+ .post_load = nrf51_timer_post_load,
+ .fields = (VMStateField[]) {
+ VMSTATE_TIMER(timer, NRF51TimerState),
+ VMSTATE_INT64(timer_start_ns, NRF51TimerState),
+ VMSTATE_INT64(update_counter_ns, NRF51TimerState),
+ VMSTATE_UINT32(counter, NRF51TimerState),
+ VMSTATE_BOOL(running, NRF51TimerState),
+ VMSTATE_UINT8_ARRAY(events_compare, NRF51TimerState,
+ NRF51_TIMER_REG_COUNT),
+ VMSTATE_UINT32_ARRAY(cc, NRF51TimerState, NRF51_TIMER_REG_COUNT),
+ VMSTATE_UINT32(shorts, NRF51TimerState),
+ VMSTATE_UINT32(inten, NRF51TimerState),
+ VMSTATE_UINT32(mode, NRF51TimerState),
+ VMSTATE_UINT32(bitmode, NRF51TimerState),
+ VMSTATE_UINT32(prescaler, NRF51TimerState),
+ VMSTATE_END_OF_LIST()
+ }
+};
+
+static void nrf51_timer_class_init(ObjectClass *klass, void *data)
+{
+ DeviceClass *dc = DEVICE_CLASS(klass);
+
+ dc->reset = nrf51_timer_reset;
+ dc->vmsd = &vmstate_nrf51_timer;
+}
+
+static const TypeInfo nrf51_timer_info = {
+ .name = TYPE_NRF51_TIMER,
+ .parent = TYPE_SYS_BUS_DEVICE,
+ .instance_size = sizeof(NRF51TimerState),
+ .instance_init = nrf51_timer_init,
+ .class_init = nrf51_timer_class_init
+};
+
+static void nrf51_timer_register_types(void)
+{
+ type_register_static(&nrf51_timer_info);
+}
+
+type_init(nrf51_timer_register_types)
diff --git a/hw/timer/trace-events b/hw/timer/trace-events
index 75bd3b1042..0144a68951 100644
--- a/hw/timer/trace-events
+++ b/hw/timer/trace-events
@@ -72,3 +72,8 @@ sun4v_rtc_write(uint64_t addr, uint64_t value) "write: addr 0x%" PRIx64 " value
# hw/timer/xlnx-zynqmp-rtc.c
xlnx_zynqmp_rtc_gettime(int year, int month, int day, int hour, int min, int sec) "Get time from host: %d-%d-%d %2d:%02d:%02d"
+
+# hw/timer/nrf51_timer.c
+nrf51_timer_read(uint64_t addr, uint32_t value, unsigned size) "read addr 0x%" PRIx64 " data 0x%" PRIx32 " size %u"
+nrf51_timer_write(uint64_t addr, uint32_t value, unsigned size) "write addr 0x%" PRIx64 " data 0x%" PRIx32 " size %u"
+
generated by cgit v1.2.3 (git 2.25.1) at 2024-11-15 20:35:37 +0000