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-rw-r--r--hw/timer/a9gtimer.c377
1 files changed, 377 insertions, 0 deletions
diff --git a/hw/timer/a9gtimer.c b/hw/timer/a9gtimer.c
new file mode 100644
index 000000000..7233068a3
--- /dev/null
+++ b/hw/timer/a9gtimer.c
@@ -0,0 +1,377 @@
+/*
+ * Global peripheral timer block for ARM A9MP
+ *
+ * (C) 2013 Xilinx Inc.
+ *
+ * Written by François LEGAL
+ * Written by Peter Crosthwaite <peter.crosthwaite@xilinx.com>
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License
+ * as published by the Free Software Foundation; either version
+ * 2 of the License, or (at your option) any later version.
+ *
+ * This program 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 General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License along
+ * with this program; if not, see <http://www.gnu.org/licenses/>.
+ */
+
+#include "qemu/osdep.h"
+#include "hw/hw.h"
+#include "hw/irq.h"
+#include "hw/qdev-properties.h"
+#include "hw/timer/a9gtimer.h"
+#include "migration/vmstate.h"
+#include "qapi/error.h"
+#include "qemu/timer.h"
+#include "qemu/bitops.h"
+#include "qemu/log.h"
+#include "qemu/module.h"
+#include "hw/core/cpu.h"
+
+#ifndef A9_GTIMER_ERR_DEBUG
+#define A9_GTIMER_ERR_DEBUG 0
+#endif
+
+#define DB_PRINT_L(level, ...) do { \
+ if (A9_GTIMER_ERR_DEBUG > (level)) { \
+ fprintf(stderr, ": %s: ", __func__); \
+ fprintf(stderr, ## __VA_ARGS__); \
+ } \
+} while (0)
+
+#define DB_PRINT(...) DB_PRINT_L(0, ## __VA_ARGS__)
+
+static inline int a9_gtimer_get_current_cpu(A9GTimerState *s)
+{
+ if (current_cpu->cpu_index >= s->num_cpu) {
+ hw_error("a9gtimer: num-cpu %d but this cpu is %d!\n",
+ s->num_cpu, current_cpu->cpu_index);
+ }
+ return current_cpu->cpu_index;
+}
+
+static inline uint64_t a9_gtimer_get_conv(A9GTimerState *s)
+{
+ uint64_t prescale = extract32(s->control, R_CONTROL_PRESCALER_SHIFT,
+ R_CONTROL_PRESCALER_LEN);
+
+ return (prescale + 1) * 10;
+}
+
+static A9GTimerUpdate a9_gtimer_get_update(A9GTimerState *s)
+{
+ A9GTimerUpdate ret;
+
+ ret.now = qemu_clock_get_ns(QEMU_CLOCK_VIRTUAL);
+ ret.new = s->ref_counter +
+ (ret.now - s->cpu_ref_time) / a9_gtimer_get_conv(s);
+ return ret;
+}
+
+static void a9_gtimer_update(A9GTimerState *s, bool sync)
+{
+
+ A9GTimerUpdate update = a9_gtimer_get_update(s);
+ int i;
+ int64_t next_cdiff = 0;
+
+ for (i = 0; i < s->num_cpu; ++i) {
+ A9GTimerPerCPU *gtb = &s->per_cpu[i];
+ int64_t cdiff = 0;
+
+ if ((s->control & R_CONTROL_TIMER_ENABLE) &&
+ (gtb->control & R_CONTROL_COMP_ENABLE)) {
+ /* R2p0+, where the compare function is >= */
+ if (gtb->compare < update.new) {
+ DB_PRINT("Compare event happened for CPU %d\n", i);
+ gtb->status = 1;
+ if (gtb->control & R_CONTROL_AUTO_INCREMENT && gtb->inc) {
+ uint64_t inc =
+ QEMU_ALIGN_UP(update.new - gtb->compare, gtb->inc);
+ DB_PRINT("Auto incrementing timer compare by %"
+ PRId64 "\n", inc);
+ gtb->compare += inc;
+ }
+ }
+ cdiff = (int64_t)gtb->compare - (int64_t)update.new + 1;
+ if (cdiff > 0 && (cdiff < next_cdiff || !next_cdiff)) {
+ next_cdiff = cdiff;
+ }
+ }
+
+ qemu_set_irq(gtb->irq,
+ gtb->status && (gtb->control & R_CONTROL_IRQ_ENABLE));
+ }
+
+ timer_del(s->timer);
+ if (next_cdiff) {
+ DB_PRINT("scheduling qemu_timer to fire again in %"
+ PRIx64 " cycles\n", next_cdiff);
+ timer_mod(s->timer, update.now + next_cdiff * a9_gtimer_get_conv(s));
+ }
+
+ if (s->control & R_CONTROL_TIMER_ENABLE) {
+ s->counter = update.new;
+ }
+
+ if (sync) {
+ s->cpu_ref_time = update.now;
+ s->ref_counter = s->counter;
+ }
+}
+
+static void a9_gtimer_update_no_sync(void *opaque)
+{
+ A9GTimerState *s = A9_GTIMER(opaque);
+
+ a9_gtimer_update(s, false);
+}
+
+static uint64_t a9_gtimer_read(void *opaque, hwaddr addr, unsigned size)
+{
+ A9GTimerPerCPU *gtb = (A9GTimerPerCPU *)opaque;
+ A9GTimerState *s = gtb->parent;
+ A9GTimerUpdate update;
+ uint64_t ret = 0;
+ int shift = 0;
+
+ switch (addr) {
+ case R_COUNTER_HI:
+ shift = 32;
+ /* fallthrough */
+ case R_COUNTER_LO:
+ update = a9_gtimer_get_update(s);
+ ret = extract64(update.new, shift, 32);
+ break;
+ case R_CONTROL:
+ ret = s->control | gtb->control;
+ break;
+ case R_INTERRUPT_STATUS:
+ ret = gtb->status;
+ break;
+ case R_COMPARATOR_HI:
+ shift = 32;
+ /* fallthrough */
+ case R_COMPARATOR_LO:
+ ret = extract64(gtb->compare, shift, 32);
+ break;
+ case R_AUTO_INCREMENT:
+ ret = gtb->inc;
+ break;
+ default:
+ qemu_log_mask(LOG_GUEST_ERROR, "bad a9gtimer register: %x\n",
+ (unsigned)addr);
+ return 0;
+ }
+
+ DB_PRINT("addr:%#x data:%#08" PRIx64 "\n", (unsigned)addr, ret);
+ return ret;
+}
+
+static void a9_gtimer_write(void *opaque, hwaddr addr, uint64_t value,
+ unsigned size)
+{
+ A9GTimerPerCPU *gtb = (A9GTimerPerCPU *)opaque;
+ A9GTimerState *s = gtb->parent;
+ int shift = 0;
+
+ DB_PRINT("addr:%#x data:%#08" PRIx64 "\n", (unsigned)addr, value);
+
+ switch (addr) {
+ case R_COUNTER_HI:
+ shift = 32;
+ /* fallthrough */
+ case R_COUNTER_LO:
+ /*
+ * Keep it simple - ARM docco explicitly says to disable timer before
+ * modding it, so don't bother trying to do all the difficult on the fly
+ * timer modifications - (if they even work in real hardware??).
+ */
+ if (s->control & R_CONTROL_TIMER_ENABLE) {
+ qemu_log_mask(LOG_GUEST_ERROR, "Cannot mod running ARM gtimer\n");
+ return;
+ }
+ s->counter = deposit64(s->counter, shift, 32, value);
+ return;
+ case R_CONTROL:
+ a9_gtimer_update(s, (value ^ s->control) & R_CONTROL_NEEDS_SYNC);
+ gtb->control = value & R_CONTROL_BANKED;
+ s->control = value & ~R_CONTROL_BANKED;
+ break;
+ case R_INTERRUPT_STATUS:
+ a9_gtimer_update(s, false);
+ gtb->status &= ~value;
+ break;
+ case R_COMPARATOR_HI:
+ shift = 32;
+ /* fallthrough */
+ case R_COMPARATOR_LO:
+ a9_gtimer_update(s, false);
+ gtb->compare = deposit64(gtb->compare, shift, 32, value);
+ break;
+ case R_AUTO_INCREMENT:
+ gtb->inc = value;
+ return;
+ default:
+ return;
+ }
+
+ a9_gtimer_update(s, false);
+}
+
+/* Wrapper functions to implement the "read global timer for
+ * the current CPU" memory regions.
+ */
+static uint64_t a9_gtimer_this_read(void *opaque, hwaddr addr,
+ unsigned size)
+{
+ A9GTimerState *s = A9_GTIMER(opaque);
+ int id = a9_gtimer_get_current_cpu(s);
+
+ /* no \n so concatenates with message from read fn */
+ DB_PRINT("CPU:%d:", id);
+
+ return a9_gtimer_read(&s->per_cpu[id], addr, size);
+}
+
+static void a9_gtimer_this_write(void *opaque, hwaddr addr,
+ uint64_t value, unsigned size)
+{
+ A9GTimerState *s = A9_GTIMER(opaque);
+ int id = a9_gtimer_get_current_cpu(s);
+
+ /* no \n so concatenates with message from write fn */
+ DB_PRINT("CPU:%d:", id);
+
+ a9_gtimer_write(&s->per_cpu[id], addr, value, size);
+}
+
+static const MemoryRegionOps a9_gtimer_this_ops = {
+ .read = a9_gtimer_this_read,
+ .write = a9_gtimer_this_write,
+ .valid = {
+ .min_access_size = 4,
+ .max_access_size = 4,
+ },
+ .endianness = DEVICE_NATIVE_ENDIAN,
+};
+
+static const MemoryRegionOps a9_gtimer_ops = {
+ .read = a9_gtimer_read,
+ .write = a9_gtimer_write,
+ .valid = {
+ .min_access_size = 4,
+ .max_access_size = 4,
+ },
+ .endianness = DEVICE_NATIVE_ENDIAN,
+};
+
+static void a9_gtimer_reset(DeviceState *dev)
+{
+ A9GTimerState *s = A9_GTIMER(dev);
+ int i;
+
+ s->counter = 0;
+ s->control = 0;
+
+ for (i = 0; i < s->num_cpu; i++) {
+ A9GTimerPerCPU *gtb = &s->per_cpu[i];
+
+ gtb->control = 0;
+ gtb->status = 0;
+ gtb->compare = 0;
+ gtb->inc = 0;
+ }
+ a9_gtimer_update(s, false);
+}
+
+static void a9_gtimer_realize(DeviceState *dev, Error **errp)
+{
+ A9GTimerState *s = A9_GTIMER(dev);
+ SysBusDevice *sbd = SYS_BUS_DEVICE(dev);
+ int i;
+
+ if (s->num_cpu < 1 || s->num_cpu > A9_GTIMER_MAX_CPUS) {
+ error_setg(errp, "%s: num-cpu must be between 1 and %d",
+ __func__, A9_GTIMER_MAX_CPUS);
+ return;
+ }
+
+ memory_region_init_io(&s->iomem, OBJECT(dev), &a9_gtimer_this_ops, s,
+ "a9gtimer shared", 0x20);
+ sysbus_init_mmio(sbd, &s->iomem);
+ s->timer = timer_new_ns(QEMU_CLOCK_VIRTUAL, a9_gtimer_update_no_sync, s);
+
+ for (i = 0; i < s->num_cpu; i++) {
+ A9GTimerPerCPU *gtb = &s->per_cpu[i];
+
+ gtb->parent = s;
+ sysbus_init_irq(sbd, &gtb->irq);
+ memory_region_init_io(&gtb->iomem, OBJECT(dev), &a9_gtimer_ops, gtb,
+ "a9gtimer per cpu", 0x20);
+ sysbus_init_mmio(sbd, &gtb->iomem);
+ }
+}
+
+static const VMStateDescription vmstate_a9_gtimer_per_cpu = {
+ .name = "arm.cortex-a9-global-timer.percpu",
+ .version_id = 1,
+ .minimum_version_id = 1,
+ .fields = (VMStateField[]) {
+ VMSTATE_UINT32(control, A9GTimerPerCPU),
+ VMSTATE_UINT64(compare, A9GTimerPerCPU),
+ VMSTATE_UINT32(status, A9GTimerPerCPU),
+ VMSTATE_UINT32(inc, A9GTimerPerCPU),
+ VMSTATE_END_OF_LIST()
+ }
+};
+
+static const VMStateDescription vmstate_a9_gtimer = {
+ .name = "arm.cortex-a9-global-timer",
+ .version_id = 1,
+ .minimum_version_id = 1,
+ .fields = (VMStateField[]) {
+ VMSTATE_TIMER_PTR(timer, A9GTimerState),
+ VMSTATE_UINT64(counter, A9GTimerState),
+ VMSTATE_UINT64(ref_counter, A9GTimerState),
+ VMSTATE_UINT64(cpu_ref_time, A9GTimerState),
+ VMSTATE_STRUCT_VARRAY_UINT32(per_cpu, A9GTimerState, num_cpu,
+ 1, vmstate_a9_gtimer_per_cpu,
+ A9GTimerPerCPU),
+ VMSTATE_END_OF_LIST()
+ }
+};
+
+static Property a9_gtimer_properties[] = {
+ DEFINE_PROP_UINT32("num-cpu", A9GTimerState, num_cpu, 0),
+ DEFINE_PROP_END_OF_LIST()
+};
+
+static void a9_gtimer_class_init(ObjectClass *klass, void *data)
+{
+ DeviceClass *dc = DEVICE_CLASS(klass);
+
+ dc->realize = a9_gtimer_realize;
+ dc->vmsd = &vmstate_a9_gtimer;
+ dc->reset = a9_gtimer_reset;
+ device_class_set_props(dc, a9_gtimer_properties);
+}
+
+static const TypeInfo a9_gtimer_info = {
+ .name = TYPE_A9_GTIMER,
+ .parent = TYPE_SYS_BUS_DEVICE,
+ .instance_size = sizeof(A9GTimerState),
+ .class_init = a9_gtimer_class_init,
+};
+
+static void a9_gtimer_register_types(void)
+{
+ type_register_static(&a9_gtimer_info);
+}
+
+type_init(a9_gtimer_register_types)