/*
* Private peripheral timer/watchdog blocks for ARM 11MPCore and A9MP
*
* Copyright (c) 2006-2007 CodeSourcery.
* Copyright (c) 2011 Linaro Limited
* Written by Paul Brook, Peter Maydell
*
* 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/ptimer.h"
#include "hw/timer/arm_mptimer.h"
#include "qapi/error.h"
#include "qemu/main-loop.h"
#include "qom/cpu.h"
#define PTIMER_POLICY \
(PTIMER_POLICY_WRAP_AFTER_ONE_PERIOD | \
PTIMER_POLICY_CONTINUOUS_TRIGGER | \
PTIMER_POLICY_NO_IMMEDIATE_TRIGGER | \
PTIMER_POLICY_NO_IMMEDIATE_RELOAD | \
PTIMER_POLICY_NO_COUNTER_ROUND_DOWN)
/* This device implements the per-cpu private timer and watchdog block
* which is used in both the ARM11MPCore and Cortex-A9MP.
*/
static inline int get_current_cpu(ARMMPTimerState *s)
{
int cpu_id = current_cpu ? current_cpu->cpu_index : 0;
if (cpu_id >= s->num_cpu) {
hw_error("arm_mptimer: num-cpu %d but this cpu is %d!\n",
s->num_cpu, cpu_id);
}
return cpu_id;
}
static inline void timerblock_update_irq(TimerBlock *tb)
{
qemu_set_irq(tb->irq, tb->status && (tb->control & 4));
}
/* Return conversion factor from mpcore timer ticks to qemu timer ticks. */
static inline uint32_t timerblock_scale(uint32_t control)
{
return (((control >> 8) & 0xff) + 1) * 10;
}
static inline void timerblock_set_count(struct ptimer_state *timer,
uint32_t control, uint64_t *count)
{
/* PTimer would trigger interrupt for periodic timer when counter set
* to 0, MPtimer under certain condition only.
*/
if ((control & 3) == 3 && (control & 0xff00) == 0 && *count == 0) {
*count = ptimer_get_limit(timer);
}
ptimer_set_count(timer, *count);
}
static inline void timerblock_run(struct ptimer_state *timer,
uint32_t control, uint32_t load)
{
if ((control & 1) && ((control & 0xff00) || load != 0)) {
ptimer_run(timer, !(control & 2));
}
}
static void timerblock_tick(void *opaque)
{
TimerBlock *tb = (TimerBlock *)opaque;
/* Periodic timer with load = 0 and prescaler != 0 would re-trigger
* IRQ after one period, otherwise it either stops or wraps around.
*/
if ((tb->control & 2) && (tb->control & 0xff00) == 0 &&
ptimer_get_limit(tb->timer) == 0) {
ptimer_stop(tb->timer);
}
tb->status = 1;
timerblock_update_irq(tb);
}
static uint64_t timerblock_read(void *opaque, hwaddr addr,
unsigned size)
{
TimerBlock *tb = (TimerBlock *)opaque;
switch (addr) {
case 0: /* Load */
return ptimer_get_limit(tb->timer);
case 4: /* Counter. */
return ptimer_get_count(tb->timer);
case 8: /* Control. */
return tb->control;
case 12: /* Interrupt status. */
return tb->status;
default:
return 0;
}
}
static void timerblock_write(void *opaque, hwaddr addr,
uint64_t value, unsigned size)
{
TimerBlock *tb = (TimerBlock *)opaque;
uint32_t control = tb->control;
switch (addr) {
case 0: /* Load */
/* Setting load to 0 stops the timer without doing the tick if
* prescaler = 0.
*/
if ((control & 1) && (control & 0xff00) == 0 && value == 0) {
ptimer_stop(tb->timer);
}
ptimer_set_limit(tb->timer, value, 1);
timerblock_run(tb->timer, control, value);
break;
case 4: /* Counter. */
/* Setting counter to 0 stops the one-shot timer, or periodic with
* load = 0, without doing the tick if prescaler = 0.
*/
if ((control & 1) && (control & 0xff00) == 0 && value == 0 &&
(!(control & 2) || ptimer_get_limit(tb->timer) == 0)) {
ptimer_stop(tb->timer);
}
timerblock_set_count(tb->timer, control, &value);
timerblock_run(tb->timer, control, value);
break;
case 8: /* Control. */
if ((control & 3) != (value & 3)) {
ptimer_stop(tb->timer);
}
if ((control & 0xff00) != (value & 0xff00)) {
ptimer_set_period(tb->timer, timerblock_scale(value));
}
if (value & 1) {
uint64_t count = ptimer_get_count(tb->timer);
/* Re-load periodic timer counter if needed. */
if ((value & 2) && count == 0) {
timerblock_set_count(tb->timer, value, &count);
}
timerblock_run(tb->timer, value, count);
}
tb->control = value;
break;
case 12: /* Interrupt status. */
tb->status &= ~value;
timerblock_update_irq(tb);
break;
}
}
/* Wrapper functions to implement the "read timer/watchdog for
* the current CPU" memory regions.
*/
static uint64_t arm_thistimer_read(void *opaque, hwaddr addr,
unsigned size)
{
ARMMPTimerState *s = (ARMMPTimerState *)opaque;
int id = get_current_cpu(s);
return timerblock_read(&s->timerblock[id], addr, size);
}
static void arm_thistimer_write(void *opaque, hwaddr addr,
uint64_t value, unsigned size)
{
ARMMPTimerState *s = (ARMMPTimerState *)opaque;
int id = get_current_cpu(s);
timerblock_write(&s->timerblock[id], addr, value, size);
}
static const MemoryRegionOps arm_thistimer_ops = {
.read = arm_thistimer_read,
.write = arm_thistimer_write,
.valid = {
.min_access_size = 4,
.max_access_size = 4,
},
.endianness = DEVICE_NATIVE_ENDIAN,
};
static const MemoryRegionOps timerblock_ops = {
.read = timerblock_read,
.write = timerblock_write,
.valid = {
.min_access_size = 4,
.max_access_size = 4,
},
.endianness = DEVICE_NATIVE_ENDIAN,
};
static void timerblock_reset(TimerBlock *tb)
{
tb->control = 0;
tb->status = 0;
if (tb->timer) {
ptimer_stop(tb->timer);
ptimer_set_limit(tb->timer, 0, 1);
ptimer_set_period(tb->timer, timerblock_scale(0));
}
}
static void arm_mptimer_reset(DeviceState *dev)
{
ARMMPTimerState *s = ARM_MPTIMER(dev);
int i;
for (i = 0; i < ARRAY_SIZE(s->timerblock); i++) {
timerblock_reset(&s->timerblock[i]);
}
}
static void arm_mptimer_init(Object *obj)
{
ARMMPTimerState *s = ARM_MPTIMER(obj);
memory_region_init_io(&s->iomem, obj, &arm_thistimer_ops, s,
"arm_mptimer_timer", 0x20);
sysbus_init_mmio(SYS_BUS_DEVICE(obj), &s->iomem);
}
static void arm_mptimer_realize(DeviceState *dev, Error **errp)
{
SysBusDevice *sbd = SYS_BUS_DEVICE(dev);
ARMMPTimerState *s = ARM_MPTIMER(dev);
int i;
if (s->num_cpu < 1 || s->num_cpu > ARM_MPTIMER_MAX_CPUS) {
error_setg(errp, "num-cpu must be between 1 and %d",
ARM_MPTIMER_MAX_CPUS);
return;
}
/* We implement one timer block per CPU, and expose multiple MMIO regions:
* * region 0 is "timer for this core"
* * region 1 is "timer for core 0"
* * region 2 is "timer for core 1"
* and so on.
* The outgoing interrupt lines are
* * timer for core 0
* * timer for core 1
* and so on.
*/
for (i = 0; i < s->num_cpu; i++) {
TimerBlock *tb = &s->timerblock[i];
QEMUBH *bh = qemu_bh_new(timerblock_tick, tb);
tb->timer = ptimer_init(bh, PTIMER_POLICY);
sysbus_init_irq(sbd, &tb->irq);
memory_region_init_io(&tb->iomem, OBJECT(s), &timerblock_ops, tb,
"arm_mptimer_timerblock", 0x20);
sysbus_init_mmio(sbd, &tb->iomem);
}
}
static const VMStateDescription vmstate_timerblock = {
.name = "arm_mptimer_timerblock",
.version_id = 3,
.minimum_version_id = 3,
.fields = (VMStateField[]) {
VMSTATE_UINT32(control, TimerBlock),
VMSTATE_UINT32(status, TimerBlock),
VMSTATE_PTIMER(timer, TimerBlock),
VMSTATE_END_OF_LIST()
}
};
static const VMStateDescription vmstate_arm_mptimer = {
.name = "arm_mptimer",
.version_id = 3,
.minimum_version_id = 3,
.fields = (VMStateField[]) {
VMSTATE_STRUCT_VARRAY_UINT32(timerblock, ARMMPTimerState, num_cpu,
3, vmstate_timerblock, TimerBlock),
VMSTATE_END_OF_LIST()
}
};
static Property arm_mptimer_properties[] = {
DEFINE_PROP_UINT32("num-cpu", ARMMPTimerState, num_cpu, 0),
DEFINE_PROP_END_OF_LIST()
};
static void arm_mptimer_class_init(ObjectClass *klass, void *data)
{
DeviceClass *dc = DEVICE_CLASS(klass);
dc->realize = arm_mptimer_realize;
dc->vmsd = &vmstate_arm_mptimer;
dc->reset = arm_mptimer_reset;
dc->props = arm_mptimer_properties;
}
static const TypeInfo arm_mptimer_info = {
.name = TYPE_ARM_MPTIMER,
.parent = TYPE_SYS_BUS_DEVICE,
.instance_size = sizeof(ARMMPTimerState),
.instance_init = arm_mptimer_init,
.class_init = arm_mptimer_class_init,
};
static void arm_mptimer_register_types(void)
{
type_register_static(&arm_mptimer_info);
}
type_init(arm_mptimer_register_types)
